Arterial hypertension incidence and outcomes in older adults of São Paulo, Brazil: SABE cohort study

Abstract

Objectives  The aim of this study was to estimate the cumulative incidence of arterial hypertension (AH) over a six-year period and to identify its risk factors and associated outcomes in older adults living in São Paulo, Brazil.

Methods  This longitudinal study utilized data from the SABE - Health, Well-being and Aging Survey of a representative probabilistic sample of older adults in the city of São Paulo. Data collection took place in 2010 and 2016. Poisson regression models were employed to assess risk factors for hypertension incidence in 2016 and to analyze the association between hypertension categories in 2010 and health outcomes throughout the 2010-2016 period.

Results  The prevalence of hypertension in 2010 was 80.4% and the incidence in 2016 was 36.1% among older adults who were normotensive in 2010. Significant positive associations were identified with age ≥75 years, prehypertension, coronary heart disease, hypercholesterolemia, and diabetes. The incidence of low glomerular filtration was the most observed health outcome in 2016 among hypertensive individuals. Uncontrolled and apparent resistant hypertension were associated with the incidence of depressive symptoms and low glomerular filtration rate over the six-year period, respectively.

Conclusions  The incidence of hypertension was high among older adults from a megalopolis of a developing country. Uncontrolled blood pressure was associated with adverse clinical and psychological health outcomes over time. The factors observed in this study should be the focus of preventive strategies implemented by healthcare services and public policies.

Keywords
Cohort Studies; Incidence; Aged; Hypertension; Chronic Disease

Resumo

Objetivos  Estimar a incidência cumulativa de hipertensão arterial (HA) em um período de seis anos, identificar fatores de risco e desfechos associados relacionados à HA na população idosa da cidade de São Paulo.

Métodos  Este estudo longitudinal utilizou dados da Pesquisa SABE - Saúde, Bem-Estar e Envelhecimento, com amostra probabilística representativa de pessoas idosas residentes na cidade de São Paulo. A coleta de dados ocorreu em 2010 e 2016. Modelos de regressão de Poisson foram empregados para avaliar os fatores de risco para a incidência de hipertensão em 2016 e para analisar a associação entre as categorias de hipertensão em 2010 e os desfechos de saúde no período 2010-2016.

Resultados  Entre as pessoas idosas normotensas em 2010, 36,1% desenvolveram HA até 2016. A incidência de HA associou-se positivamente à idade ≥75 anos, pré-hipertensão, doença coronariana, hipercolesterolemia e diabetes. A baixa filtração glomerular foi o desfecho de saúde mais observado em 2016 entre os hipertensos. Hipertensão não controlada e hipertensão resistente aparente foram associadas à incidência de sintomas depressivos e redução da taxa de filtração glomerular no período de seis anos, respectivamente.

Conclusões  A incidência de hipertensão foi elevada na população idosa de uma megalópole de um país em desenvolvimento. O descontrole da pressão arterial foi associado a resultados adversos de saúde clínica e psicológica ao longo do tempo. Os fatores observados neste estudo devem ser foco de estratégias preventivas implementadas pelos serviços de saúde e pelas políticas públicas.

Palavras-Chave:
Estudos De Coortes; Incidência; Pessoa Idosa; Hipertensão Arterial; Doença Crônica

INTRODUCTION

Arterial hypertension (AH) affects a substantial proportion of adults globally, particularly in socioeconomically disadvantaged contexts, posing a significant public health challenge due to its low rates of control among older adults¹-³. An estimated 60% of the world population aged 60 or older has hypertension, with rates exceeding 70% in octogenarians³,⁴. Prevalence studies in Brazil show that the main characteristics associated with AH are being female, aged 70 years or older, having non-white skin color and pre-existing chronic diseases⁵.

Elevated blood pressure (BP) levels during life are associated with increased risk of fatal and non-fatal health outcomes⁶. However, there is a lack of epidemiological population-based data on AH incidence, particularly in low and middle-lower income countries. To date, only one cohort study in Brazil⁷ has specifically investigated AH incidence in older adults, whereas no cohort studies evaluating the association between AH and outcomes except mortality werefound⁸.

The aim of this study was to estimate the prevalence of AH among individuals aged 60 or older living in the city of São Paulo, together with the cumulative incidence of AH over a six-year period among participants who were initially normotensive, identifying risk factors. Also, the association between AH levels in 2010 and the incidence of fatal and non-fatal health outcomes in 2016 were investigated.

METHODOLOGY

Study design and population

This longitudinal study utilized data from the “SABE – Health, Well-being and Aging Survey”, a multiple-cohort study initiated in 2000 involving a probabilistic sample of older individuals (≥60 years) living in the city of São Paulo. The study drew on data collected in 2010 and 2016, when BP measurements were introduced. A two-stage cluster sampling approach, with clusters allocated proportionally based on census sector size and residence, was employed ⁹.

All information regarding sample size determination, methods and sample weights of the study waves can be found in Lebrão⁹. In the first wave, the number of participants was proposed by the Pan American Health Organization (PAHO) for the multicenter study (n=1500), in addition to oversampling of older adults aged 75 or over. The sample size of cohort B in 2006 was estimated based on the prevalence of hypertension in 2000 (50%), on a design effect of 1.5, and margin of error of 7%. For calculating cohort C in 2010, the same process was used based on the population aged 60-64 years in 2010 (413,563), according to census data⁹. Of the 2,143 older people interviewed in 2000 (cohort A00), 1,115 people were located and re-interviewed in 2006 (cohort A06) and 748 in 2010 (cohort A10). In addition to revaluation of cohort A in subsequent study waves, the SABE survey included new cohorts of people aged 60-64 residing in the urban area of São Paulo in the years 2006 (cohort B06 n=298 in 2006, with re-interviews of B10 n=230 in 2010) and 2010 (cohort C10 n=356). A new cohort of people aged 60-64 was added in the fourth wave (2016), but not included in this analysis. For the present study, data on participants from cohorts A10, B10 and C10 were used, as these were reevaluated in 2016. Sample weights were calculated in 2010 so that the interviewees represented the older population of São Paulo in 2010, according to census information.

Trained professionals conducted home visits to apply the questionnaires. Blood samples were collected and physical evaluations performed, including three BP measurements. BP was measured using a HEM-75CP Intellisense digital pressure monitor after an initial 5-minute rest. Individuals were instructed on the appropriate position to perform the BP measurements, and three measurements were taken, with a one-minute interval between each. The size of the blood pressure cuff used was chosen according to the participant´s arm circumference. The first BP measurement was excluded, and the final BP value was the average of the last two measurements. Regarding waist circumference, a standard measuring tape was positioned between the iliac crest and lower ribs. For the procedure, the individual stood upright, with legs apart, a relaxed abdomen and arms extended alongside the body. Three measurements were taken, and the mean of these was used as the final value.

The SABE (Health, Wellbeing, and Aging) survey was approved by the Research Ethics Committee of the School of Public Health, University of São Paulo, for all waves of data collection. The data used in this study were approved under protocols no. 2.044 (2010) and no. 3.600.782 (2016). All participants or their guardians signed the written informed consent form previously approved by the Research Ethics Committee and all personal information was treated as confidential.

Variables

Arterial hypertension: the absence of AH in 2010 was determined by a negative response to the question “Has a doctor or nurse ever said that you have hypertension?”, mean BP of <140/90mmHg, and no antihypertensive medication use, according to the Anatomical Therapeutic Chemical Classification System (ATC)¹⁰. Normotensive individuals had systolic blood pressure (SBP) <130mmHg and diastolic blood pressure (DBP) <85 mmHg, while prehypertensive individuals had SBP = 130-139 mmHg and DBP = 85-89 mmHg.

Hypertensive individuals were classified according to the Brazilian Guidelines for AH¹¹: Stage 1 (SBP = 140-159 mmHg and/or DBP = 90-99 mmHg), Stage 2 (SBP = 160-179 mmHg and/or DBP = 100-109 mmHg) and Stage 3 (SBP≥180 mmHg and/or DBP≥110 mmHg). Controlled hypertension was defined as hypertensive individuals with BP <140/90 mmHg.

Incident cases of AH were defined as individuals without AH in 2010 according to reported diagnosis, and a subsequent mean BP ≥140/90 mmHg, or use of antihypertensive medication, in 2016.

To analyze the association of AH with outcomes, individuals were classified according to their BP in 2010 as follows: normotensive (normal/prehypertensive), controlled (BP <140/90 mmHg in hypertensive individuals), uncontrolled (BP ≥140/90 mmHg), and apparent resistant hypertension (BP≥ 140/90mmHg, while using ≥3 antihypertensive classes, or ≥4 antihypertensive classes regardless of BP)¹².

The sociodemographic characteristics evaluated were sex, age (60-74, ≥75 years), and education (0-3, 4-7, ≥8 years).

The health characteristics assessed were diabetes (reported and/or fasting glycemia ≥126 mg/dl and/or glycated hemoglobin ≥6.5%), coronary and cerebrovascular diseases (reported), isolated hypercholesterolemia (LDL cholesterol>160 mg/dl and/or use of lipid-lowering agents), elevated triglycerides (fasting levels >150 mg/dL), elevated uric acid (>7 mg/dL in men and >5.7 mg/dL in women)¹¹, cognitive decline (≤12 points on the Mini-Mental State Examination (MMSE), adapted for the SABE Study)¹³, low glomerular filtration rate (GFR) (<60 mL/min/1.73 m², estimated by the CKD-EPI creatinine equation)¹⁴, and presence of depressive symptoms (score ≥ 6 on the 15-item Geriatric Depression Scale (GDS))¹⁵.

Anthropometry and life habits probed were smoking history (never smoked, smokers/ex-smokers), alcohol consumption (yes/no), physical activity (sufficiently active if ≥150 minutes of moderate and/or vigorous physical activity per week according to the International Physical Activity Questionnaire – IPAQ)¹⁶, and elevated waist circumference (WC) (>102 cm for men and >88 cm for women)¹¹.

Utilization of health services was assessed based on doctor’s visits (yes/no) and hospitalization due to hypertension (yes/no) in the previous year.

The health outcomes examined included newly reported coronary or cerebrovascular events in 2016 or registered deaths between 2010 and 2016, corresponding to ICD-10 I25, I25.0, I25.1, I25.2, I25.3, I25.4, I25.5, I25.6, I25.8 and I25.9, I21, I21.0, I21,1, I21.2, I21.3, I24.4 and I21.9, I63.9, I69.3, I64 and I69.4 in the Mortality Information Improvement Program of the City of São Paulo¹⁷. Cases with deaths due to external or unknown causes were excluded from the analyses. Other outcomes assessed were cognitive decline (score <12 on the MMSE in 2016 for individuals who scored ≥12 in 2010), depressive symptoms (score ≥6 on the GDS in 2016 in individuals who scored <6 in 2010) and low GFR (<60 mL/min/1.73m² in 2016 in individuals with GFR ≥60 in 2010).

Statistical Analysis

Out of the 1344 participants evaluated in 2010, a total of 308 had deceased and 200 were lost for reasons of refusal, unable to locate, change of address, or institutionalization, giving 836 participants re-evaluated in 2016. Among the initial 1344 participants, 229 were normotensive in 2010, with 152 participants remaining in the study until 2016, constituting the sample for estimating the cumulative incidence of AH. To ensure the representativeness of the population within the sample, all analyses incorporated sampling weights calculated for the SABE Study in 2010, and weighted proportions were reported. Group comparisons were conducted using the Rao-Scott chi-square test.

Poisson regression analysis was employed to assess the association between AH incidence (reference: normotensive participants in both waves) and independent variables measured in 2010. Variables with p-value<0.20 on univariate analysis were included in the multiple regression model. A 95% confidence interval (95%CI) was adopted. The initial model included age, education, BP level, WC, triglycerides, diabetes, coronary diseases, hypercholesterolemia, doctor’s visit within the past year, and alcohol consumption, adjusting for sex. The model was built using a backward selection process, retaining variables that induced ≥10% alteration in the beta coefficients of other variables upon their removal.

Poisson regression was also used to evaluate the association between AH in 2010 and the incidence of outcomes in 2016. Crude models initially included AH categories (exposure) and specific outcome, followed by the addition of demographic, socioeconomic and health variables for further adjustment.

DATA AVAILABILITY

The datasets analyzed in the current study were used under license and are not publicly available due to the policies of the SABE Study.

RESULTS

At baseline, 96 participant records had missing data regarding self-report or BP measurements and were therefore excluded from subsequent analyses. In 2010, the prevalence of hypertension among older adults from São Paulo was 80.4%, while the rate of controlled hypertension (CH) was 33.8%, uncontrolled hypertension (UH) 38.7%, and apparent resistant hypertension (ARH) 7.9%. Hypertensive individuals were older and had lower educational level, whereas those with ARH had a higher prevalence of diabetes and hypercholesterolemia, as well as high WC (Table 1).

Table 1
Baseline description of the main life and health characteristics, according to the arterial hypertension (AH) categories, of older adults living in São Paulo in 2010. São Paulo city, São Paulo state, 2010.

Variables	Total* (n=1,236,465) (%)	Normotensive (n=242,019) (%)	Controlled AH (n=417,965) (%)	Uncontrolled AH (n=478,172) (%)	Apparent resistant AH (n=98,308) (%)	p-value**
Sex
Female	60.5	57.2	66.0	57.8	58.9	0.095
Age
60-74	75.5	84.0	73.2	75.2	66.6
≥75	24.5	16.0	26.8	24.8	33.4	0.001
Education (years)
0-3	36.2	26.6	35.2	39.2	49.3
4-7	37.7	35.9	38.8	37.2	39.5
≥ 8	26.1	37.5	26.0	23.6	11.2	<0.001
Diabetes
Yes	29.0	12.9	29.7	30.5	58.6	<0.001
Isolated hypercholesterolemia
Yes	37.2	36.4	40.6	32.3	48.1	0.017
High uric acid level
	19.7	8.3	23.2	18.4	23.6	<0.001
High waist circumference
	52.6	46.5	54.2	50.8	69.8	0.004
High triglycerides
	30.8	27.5	31.6	31.0	35.2	0.622
Smoking history
Smokers and ex-smokers	49.3	44.9	48.1	52.6	48.9	0.313
Physical activity
Sufficiently active	43.3	42.8	40.7	44.7	48.9	0.523
Alcohol use in last 3 months
Yes	30.6	35.5	28.0	32.4	21.1	0.068
Doctor’s visit in last year
Yes	87.5	82.4	93.1	82.8	99.1	<0.001
Chronic diseases ¶
0	31.5	42.6	27.0	33.8	11.6
1	33.5	31.8	31.9	36.4	30.1
≥ 2	35.0	25.6	41.1	29.8	58.3	<0.001
Antihypertensive classes in use #
0	21.4	-	8.1	33.0	-
1	42.5	-	43.6	41.6	-
≥ 2	36.1	-	48.3	25.4	-	<0.001
Stages of AH
Stage 1	58.6	-	-	60.9	45.4
Stage 2	30.3	-	-	28.1	43.2
Stage 3	11.1	-	-	11.0	11.4	<0.001
Hospitalization due to AH ¥
Yes	13.1	-	12.9	10.5	22.8	<0.001

• * Weighted N represents older adult population of São Paulo; **Rao-Scott chi-square test; ¶Diabetes, coronary heart diseases, cerebrovascular diseases, pulmonary diseases, articular diseases, psychiatric diseases, cancer; # Individuals with resistant hypertension were not considered because all used at least 3 classes of antihypertensives; ¥ In past year.

The most common stage of hypertension observed in 2010 was stage 1, proving more prevalent among individuals with UH, while stage 2 was more common in those with ARH. Approximately one-fifth of the ARH group reported at least one hospitalization due to hypertension in the previous year, twice the rate of individuals with CH or UH (Table 1).

One-third of older individuals with UH in 2010 were not taking any medication, while half of those with CH were taking ≥2 medications for BP control. Diuretics and angiotensin-converting enzyme (ACE) inhibitors were commonly used across all hypertension categories (38.5% and 39.5% respectively). ACE inhibitors were used by 45.8%, 29.6% and 84.4% of individuals with CH, UH and ARH, respectively. Among participants with ARH, 73% used calcium channel blockers.

Of the participants without hypertension in 2010, 73% were normotensive and 27% prehypertensive. The cumulative incidence of AH between 2010 and 2016 was 36.1% (95%CI 28.3 – 44.8), compared with 31.6% among normotensive and 47.8% among prehypertensive individuals in 2010. More than half of the cases with incident AH were undiagnosed and had uncontrolled BP in 2016 (Table 2).

Table 2
Diagnosis, treatment, and control in older people with incident arterial hypertension (AH) in São Paulo in 2016. São Paulo city, São Paulo state, 2010-2016.

	Total cases of incident hypertension in 2016 (n=63,121) (%)*	Cases of incident hypertension in 2016 among normotensives in 2010 (n=40,245) (%)	Cases of incident hypertension in 2016 among prehypertensives in 2010 (n=22,876) (%)	p-value**
Reported hypertension diagnosis (2016)
Yes	41.2	39.1	44.7	0.705
Controlled AH (2016)
Yes	44.3	41.7	48.9	0.633
Stages of hypertension (2016)¶
Stage 1	62.6	63.9	59.8
Stages 2 and 3	37.4	36.1	40.2	0.849
Type of pharmacological treatment for AH (2016)
Not in use of medication	44.1	46.7	39.4
Monotherapy	43.4	43.5	43.3
> 1 medication	12.5	9.8	17.4	0.719

• * Weighted N represents incident cases in older adult population from São Paulo; ** Rao-Scott chi-square test; ¶ Among uncontrolled hypertensives (55.7% of individuals with incident hypertension).

Of the incident cases, 56% were using antihypertensive medication in 2016, predominantly beta-blockers (23.8%) and diuretics (15.5%). Calcium channel blockers were less frequently used (2.9%). Non-pharmacological strategies for AH treatment, including dietary changes and physical activity, were reported by 46.9% and 23.1% of participants, respectively. Factors associated with incident AH included age ≥75 years, prehypertension, isolated hypercholesterolemia, diabetes, and coronary disease in 2010, while at least one doctor’s visit in the past year was associated with a lower incidence of hypertension (Table 3).

Table 3
Factors associated with arterial hypertension incidence in 2010-2016 period. São Paulo city, São Paulo state, 2010-2016.

	Crude IRR* (95% CI)**	p-value	Adjusted IRR*¶ (95% CI)**	p-value
Age
≥75	1.9 (1.3 - 3.0)	0.001	1.9 (1.2 - 2.9)	0.007
60-74	1		1
Blood pressure levels
Prehypertensive	1.5 (0.9 - 2.4)	0.083	1.6 (1.0 - 2.6)	0.033
Normotensive	1		1
Coronary heart disease
Yes	1.8 (1.1 - 3.1)	0.027	2.3 (1.5 - 3.6)	<0.001
No	1		1
Isolated hypercholesterolemia
Yes	1.3 (0.8 - 2.1)	0.214	1.5 (1.1 - 2.4)	0.047
No	1		1
Diabetes
Yes	1.6 (0.9 - 2.6)	0.091	1.9 (1.1 - 3.1)	0.009
No	1		1
Doctor’s visits in the past year
Yes	0.6 (0.4 - 1.1)	0.117	0.5 (0.3 - 0.9)	0.026
No	1		1

• * IRR = incidence rate ratio; **CI = Confidence interval. ¶ Final model (age group + blood pressure level + coronary heart disease + hypercholesterolemia + diabetes and doctor's visit) adjusted for gender and all non-significant independent variables (triglycerides, waist circumference, alcohol use). Independent variables were measured at baseline, in 2010.

Health outcomes between 2010 and 2016 were more frequent among hypertensive individuals compared to normotensive individuals in 2010. Low GFR was the most commonly observed outcome. Hypertensive individuals, with controlled and uncontrolled BP, had a higher rate of depressive symptoms than normotensive individuals, and death was more frequent among individuals with ARH (Table 4).

Table 4
Hypertension-related outcomes according to previous arterial hypertension (AH) category in 2010. São Paulo city, São Paulo state, 2010-2016.

Incidence of outcomes in 2016*	Total (%)	Normotensive in 2010 (%)	Controlled AH in 2010 (%)	Uncontrolled AH in 2010 (%)	Resistant AH in 2010 (%)	p-value**
Coronary heart events¶	18.3	13.4	19.5	18.9	29.3	0.164
Cerebrovascular events¶	4.9	2.9	5.1	6.3	3.0	0.343
GFR <60#	22.2	17.1	22.7	22.5	39.1	0.091
Cognitive decline	13.2	8.6	12.6	15.9	16.3	0.193
Depressive symptoms	10.7	6.0	12.1	13.5	4.1	0.048
Deaths (all causes)	17.3	13.2	17.7	16.6	28.3	0.010

• *Only in individuals without these characteristics in 2010 and reevaluated in 2016 or that died during the period due to outcome evaluated; ** Rao-Scott chi-square test; ¶ Newly-reported disease in 2016 or registered deaths by this disease in 2010-2016 period; # Glomerular Filtration Rate.

At 6-year follow-up, the risk of low GFR in 2016 among participants with GFR ≥60mL/min/1.73m² and ARH in 2010 was 2.1 times greater than that of individuals without hypertension. In individuals with UH in 2010, the risk of developing depressive symptoms was 2.1 times greater than that of participants without hypertension (Table 5).

Table 5
Results of Poisson regression models for association between hypertension categories in 2010 and incidence of glomerular filtration rate (GFR) <60mL/min/1.73m2* and depressive symptoms** in 2016. São Paulo city, São Paulo state, 2010-2016.

Hypertension categories in 2010	Crude model for incidence of low GFR (95% CI)¶	Adjusted model 1# IRR (95% CI)	Adjusted model 2¥ IRR (95% CI)
Controlled	1.3 (0.8 - 2.2)	1.3 (0.8 - 2.1)	1.2 (0.7 - 2.0)
Uncontrolled	1.3 (0.8 - 2.1)	1.2 (0.7 - 1.9)	1.2 (0.7 - 2.0)
Apparent resistant	2.3 (1.2 - 4.2)	2.2 (1.2 - 4.1)	2.1 (1.1 - 4.0)
Normotensive	1	1	1
	Crude model for incidence of depressive symptoms (95% CI)	Adjusted model 1# IRR (95% CI)	Adjusted model 2¥ IRR (95% CI)
Controlled	2.0 (0.9 - 4.3)	1.8 (0.8 - 3.9)	1.8 (0.8 - 3.9)
Uncontrolled	2.3 (1.1 - 4.6)	2.1 (0.9 - 4.3)	2.1 (1.1 - 4.4)
Apparent resistant	0.7 (0.2 - 2.5)	0.6 (0.2 - 2.2)	0.6 (0.1 - 2.2)
Normotensive	1	1	1

• * Among individuals with GFR≥60mL/min/1.73m2 in 2010; **Among individuals scoring <6 on Geriatric Depression Scale in 2010; ¶ 95% Confidence intervals; #Adjusted for gender, age group and education; ¥ Adjusted for variables in model 1+ physical activity, waist circumference, diabetes, smoking habit, alcohol use and hypercholesterolemia.

DISCUSSION

In this study of a representative sample of older adults from the city of São Paulo, a high prevalence of AH was observed, with a predominance of UH. Notably, over one-third of normotensive individuals in 2010 went on to develop AH by 2016, with worse health status and prehypertension significantly increasing the risk of developing AH. The health outcomes assessed in 2016 were generally more prevalent among individuals with ARH and UH.

As expected, a high prevalence of UH was found in 2010². The presence of comorbidities and age-related physiological changes can hamper BP control in older adults. In the present study, 7.9% of participants (9.9% of hypertensive individuals) met the criteria for ARH, consistent with the definition used in other population studies¹²,¹⁸. This prevalence surpassed the 6.5% rate reported in a prospective cohort study of older individuals in France¹⁹. Global prevalence of ARH among hypertensive individuals ranges from 10% to 20%, depending on the definition applied²⁰.

The cumulative incidence of hypertension in the present study was 36%, with an average annual increase of 6%, lower than rates in previous studies using similar diagnostic criteria, such as the 37.7% cumulative incidence reported in a five-year study of Koreans aged ≥65 years (average increase of 7.5% per year)²¹.

In the current study, approximately half of the prehypertensive individuals progressed to hypertension between 2010 and 2016, representing an average annual increase of 8% and a 60% higher risk compared to individuals who were normotensive in 2010. This rate of progression was higher than that found in a study conducted in Taiwan²², where 31.3% of prehypertensive participants (mean age 64.4 years) developed hypertension over five years (average annual increase of 6.3%). However, the Framingham Study, after a four-year follow-up of prehypertensive individuals, reported an even higher progression rate and a cumulative incidence of 49.5% among individuals aged ≥65 years (average annual increase of 12.4%)²³.

Participants aged ≥75 years had a 90% higher risk of developing hypertension, aligning with the notion that advanced age is a significant risk factor for AH onset due to physiological changes and lifelong exposure to risk factors⁵.

Only 56% of incident hypertension cases were using antihypertensive medications, reflecting challenges in pharmacological treatment adherence, possibly influenced by factors such as limited knowledge about AH and unfavorable socioeconomic conditions such as low educational levels²⁴. Having a higher educational level is often associated with greater rates of diagnosis and treatment of AH, health literacy and use of health services, including the acquisition of private healthcare²⁴-²⁶. Also, the use of BP to identify AH in this study may have improved the detection of incident cases, contributing to the low use of pharmacological treatment observed.

Older adults with recent doctor’s visits in 2010 had a 50% lower risk of incident AH, emphasizing the role of healthcare access in better health outcomes in older age²⁷. Greater access enables the planning of preventive strategies and improved management of pre-established diseases.

Isolated hypercholesterolemia was associated with AH incidence, consistent with the findings of a 12-year study of Korean older adults²⁸. Besides cholesterol, evidence suggests an association of AH incidence with triglyceride and uric acid levels²⁹,³⁰, although these associations were not observed in the present study.

Having diabetes increased the risk of developing hypertension by 90%. Despite the common risk factors shared by these diseases, diabetic individuals can also have increased arterial stiffness and cardiometabolic disorders linked to hypertension incidence³¹. Pre-existing coronary heart disease was also associated with incident AH in 2016. More than 40% of the individuals evaluated in 2010 presented characteristics such as hypercholesterolemia and high WC, conditions which may have contributed to the occurrence of coronary heart diseases even before the onset of AH.

Among the individuals with a GFR ≥60 mL/min/1.73m² in 2010, over one-fifth had a GFR <60 in 2016, where those with prior ARH had a 2.1 times greater risk of low GFR in 2016. A cohort study of North Americans aged ≥50 years also reported a higher frequency of this outcome among individuals with ARH compared to those with non-resistant hypertension³². The presence of ARH is associated with worsening renal function in older adults, as well as increased cardiovascular and renal mortality, even in younger individuals¹⁸,³³.

Uncontrolled hypertension was associated with depressive symptoms incidence in 2016, although the association between UH and depressive symptoms remains a matter of debate. In a two-year follow-up study, hypertensive individuals aged ≥60 in Mexico had an 18% higher risk of developing depressive symptoms compared to normotensive individuals³⁴. Cerebral white matter lesions caused by AH may partially explain the emergence of depressive symptoms in hypertensive individuals over time³⁴. However, no longitudinal studies specifically examining the association between UH and the incidence of depressive symptoms in this age group were found.

Frequent outcomes between 2010 and 2016 included the incidence of coronary events and all-cause mortality. While an association of AH with overall mortality has been reported³⁵, this study failed to observe a relationship between various hypertension categories and coronary events (including deaths) or mortality.

The focus of the SABE survey on the population aged ≥60 distinguishes it from other population-based studies where assessment of older adults is secondary, lacking a dedicated sample for this age group. The methodology of this survey included collection of biochemical information and BP measurements, allowing for the use of data beyond self-reported information. Moreover, it is important to note that longitudinal studies involving older adults with AH are underexplored in the literature due to the challenges associated with conducting such investigations, including their costs, need for a large research infrastructure and for long-term observation.

Despite its strengths, the present study also has limitations. BP was measured only once during each data collection wave. Reported diagnosis and antihypertensive medication usage were also used for more accurate identification of cases of AH. To minimize the potential influence of the “white-coat syndrome”, the first BP measurement was excluded from the analysis. The substantial number of losses between study waves, a common phenomenon in cohort studies involving older adults, constitutes an additional constraint. This characteristic may have resulted in an underestimation of the incidence of AH and hampered the analysis of outcomes beyond mortality. Those individuals lost to follow-up, predominantly due to mortality, were older and had more comorbidities compared to those who were retained in the study. Although these losses may introduce survival bias in the estimates, they represent an intrinsic unavoidable component of longitudinal studies involving the older population.

CONCLUSIONS

This longitudinal study provided a comprehensive picture of the older population residing in the city of São Paulo for both hypertension stages and control.

In summary, the cumulative incidence of hypertension from 2010 to 2016 was 36%, with a higher incidence among prehypertensive individuals. The disease was also associated with the presence of unfavorable health characteristics at baseline assessment. Conversely, older individuals with recent healthcare visits had a lower incidence of hypertension.

Hypertensive older adults had elevated mortality rates. Participants with uncontrolled hypertension and apparent resistant hypertension in 2010 had an increased risk of developing depressive symptoms and reduced renal function in 2016, even after adjusting for demographic, socioeconomic and health-related variables.

Longitudinal studies play a critical role in assessing the risk factors associated with hypertension incidence, which cannot be overstated, given the substantial impact of this condition on the well-being of older adults. Prehypertension emerges as an intermediate factor predisposing individuals to hypertension, highlighting the role of blood pressure control as a target for preventive interventions by healthcare professionals, teams, services, and policies. Additionally, evaluating the association between hypertension and both fatal and non-fatal outcomes emphasizes the importance of the prevention and control strategies for hypertension, with the overarching goal of mitigating associated consequences.

Lastly, this comprehensive investigation provides valuable insights into the prevalence, incidence and outcomes of hypertension among the older population. The study findings can contribute to the formulation and enhancement of preventive strategies for healthcare, both at individual and population levels, emphasizing the importance of initiatives for early detection and improved blood pressure control at the primary care level to mitigate fatal and non-fatal outcomes.

• Funding: The São Paulo Research Foundation (FAPESP) - SABE Study 2010: Health, well-being and aging. Process number: 09/53778-3. This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (CAPES) – Finance Code 001.
• DATA AVAILABILITY
  The datasets analyzed in the current study were used under license and are not publicly available due to the policies of the SABE Study.

References

• ¹ Mills KT, Stefanescu A, He J. The global epidemiology of hypertension. Nat Rev Nephrol. 2020; 223–237. Disponível em: https://doi.org/10.1038/s41581-019-0244-2
  » https://doi.org/10.1038/s41581-019-0244-2
• ² Firmo JOA, Peixoto SV, Loyola Filho AI, Souza-Júnior PRB de, Andrade FB de, Lima-Costa MF, et al. Comportamentos em saúde e o controle da hipertensão arterial: resultados do ELSI-BRASIL. Cad Saúde Pública. 2019;35:e00091018. Disponível em: https://doi.org/10.1590/0102-311X00091018
  » https://doi.org/10.1590/0102-311X00091018
• ³ Malachias MVB. The challenges of controlling arterial hypertension in the elderly. Arq Bras Cardiol. 2019;112(3):279–80. Disponível em: https://doi.org/10.5935/abc.20190020
  » https://doi.org/10.5935/abc.20190020
• ⁴ Oliveros E, Patel H, Kyung S, et al. Hypertension in older adults: Assessment, management, and challenges. Clin Cardiol. 2020;43(2):99-107. Disponível em: https://doi.org/10.1002/clc.23303
  » https://doi.org/10.1002/clc.23303
• ⁵ Bento IC, Mambrini JV de M, Peixoto SV. Fatores contextuais e individuais associados à hipertensão arterial entre idosos brasileiros (Pesquisa Nacional de Saúde - 2013). Rev bras epidemiol. 2020;23:e200078. Disponível em: https://doi.org/10.1590/1980-549720200078
  » https://doi.org/10.1590/1980-549720200078
• ⁶ Flint AC, Conell C, Ren X, Banki NM, Chan SL, Rao VA, et al. Effect of systolic and diastolic blood pressure on cardiovascular outcomes. N Engl J Med. 2019;381(3):243-251. Disponível em: https://doi.org/10.1056/NEJMoa1803180
  » https://doi.org/10.1056/NEJMoa1803180
• ⁷ Freitas MPD, Loyola Filho AI de, Lima-Costa MF. Dyslipidemia and the risk of incident hypertension in a population of community-dwelling Brazilian elderly: the Bambuí cohort study of aging. Cad Saúde Pública. 2011;27 Suppl 3:S351-9. Disponível em: https://doi.org/10.1590/s0102-311x2011001500005
  » https://doi.org/10.1590/s0102-311x2011001500005
• ⁸ De Oliveira C, Marmot MG, Demakakos P, Vaz de Melo Mambrini J, Peixoto SV, Lima-Costa MF. Mortality risk attributable to smoking, hypertension and diabetes among English and Brazilian older adults (The ELSA and Bambui cohort ageing studies). Eur J Public Health. 2016; 26(5):831-835. Disponível em: https://doi.org/10.1093/eurpub/ckv225
  » https://doi.org/10.1093/eurpub/ckv225
• ⁹ Lebrão ML, Duarte YAO, Santos JLF, Silva NND. 10 Years of SABE Study: background, methodology and organization of the study. 10 Anos do Estudo SABE: antecedentes, metodologia e organização do estudo. Rev Bras Epidemiol. 2018; 21 Suppl02:e180002. Disponível em: https://doi.org/10.1590/1980-549720180002.supl.2.
  » https://doi.org/10.1590/1980-549720180002.supl.2
• ¹⁰ World Health Organization - Collaborating Centre for Drug Statistics Methodology. ATC/DDD Index. [Acessado 7 Jun. 2023]. Disponível em: https://www.whocc.no/atc_ddd_index/ .
  » https://www.whocc.no/atc_ddd_index/
• ¹¹ Barroso W, Rodrigues C, Bortolotto LA, Mota-Gomes MA, Brandão AA, Feitosa ADM, et al. Diretrizes Brasileiras de Hipertensão Arterial – 2020. Arq Bras Cardiol. 2021;116:516–658. Disponível em: https://doi.org/10.36660/abc.20201238
  » https://doi.org/10.36660/abc.20201238
• ¹² Fay KS, Cohen DL. Resistant Hypertension in People With CKD: A Review. Am J Kidney Dis. 2021;77(1):110-121. Disponível em: https://doi.org/10.1053/j.ajkd.2020.04.017
  » https://doi.org/10.1053/j.ajkd.2020.04.017
• ¹³ Icaza MC, Albala C. Projeto SABE Minimental State Examination (MMSE) del estudio de dementia en Chile: análisis estatístico. Washington: Organización Panamericana de la Salud, 1999.
• ¹⁴ Levey AS, Stevens LA, Schmid CH, Zhang YL, Castro AF 3rd, Feldman HI, et al. A new equation to estimate glomerular filtration rate. Ann Intern Med. 2009; 150:604–612. Disponível em: https://doi.org/10.7326/0003-4819-150-9-200905050-00006
  » https://doi.org/10.7326/0003-4819-150-9-200905050-00006
• ¹⁵ Sheikh JI, Yesavage JA. Geriatric Depression Scale (GDS): recent evidence and development of a shorter version. Clin Gerontol. 1986; 5: 165-173. Disponível em: https://doi.org/10.1300/J018v05n01_09
  » https://doi.org/10.1300/J018v05n01_09
• ¹⁶ Matsudo S, Araujo T, Matsudo V, Andrade D, Andrade E, Oliveira LC, et al. Questionário Internacional de Atividade Física (IPAQ): estudo de validade e reprodutibilidade no Brasil. Rev Bras Ativ Fís Saúde. 2001; 6:5-18. Disponível em: https://rbafs.org.br/RBAFS/article/view/931
• ¹⁷ Roman Lay AA, do Nascimento CF, Duarte YAO, Porto Chiavegatto Filho AD. Age at natural menopause and mortality: A survival analysis of elderly residents of São Paulo, Brazil. Maturitas. 2018;117: 29–33. Disponível em: https://doi.org/10.1016/j.maturitas.2018.08.012
  » https://doi.org/10.1016/j.maturitas.2018.08.012
• ¹⁸ Tanner RM, Calhoun DA, Bell EK, Bowling CB, Gutiérrez OM, Irvin MR, et al. Prevalence of apparent treatment-resistant hypertension among individuals with CKD. J Am Soc Nephrol. 2013; 8:1583–1590. Disponível em: https://doi.org/10.2215/CJN.00550113
  » https://doi.org/10.2215/CJN.00550113
• ¹⁹ Kaboré J, Metzger M, Helmer C, et al. Kidney function decline and apparent treatment-resistant hypertension in the elderly. PLoS One. 2016;11(1):e0146056. Disponível em: https://doi.org/10.1371/journal.pone.0146056
  » https://doi.org/10.1371/journal.pone.0146056
• ²⁰ Brant LCC, Passaglia LG, Pinto-Filho MM et al. The burden of resistant hypertension across the world. Curr Hypertens Rep. 2022; 24:55–66. Disponível em: https://doi.org/10.1007/s11906-022-01173-w
  » https://doi.org/10.1007/s11906-022-01173-w
• ²¹ Lee JH, Yang DH, Park HS, Cho Y, Jun JE, Park WH, et al. Incidence of hypertension in Korea: 5-year follow-up study. J Korean Med Sci. 2011; 26:1286–1292. Disponível em: https://doi.org/10.3346/jkms.2011.26.10.1286
  » https://doi.org/10.3346/jkms.2011.26.10.1286
• ²² Liu LK, Peng LN, Chen LK, Hwang SJ, Chiou ST. Prehypertension among middle-aged and elderly people in Taiwan: a five-year follow-up. J Atheroscler Thromb. 2010; 17: 189–194. Disponível em: https://doi.org/10.5551/jat.2832
  » https://doi.org/10.5551/jat.2832
• ²³ Vasan RS, Larson MG, Leip EP, Kannel WB, Levy D. Assessment of frequency of progression to hypertension in non-hypertensive participants in the Framingham Heart Study: a cohort study. Lancet. 2001; 358:1682–1686. Disponível em: https://doi.org/10.1016/S0140-6736(01)06710-1
  » https://doi.org/10.1016/S0140-6736(
• ²⁴ Parra DI, Romero Guevara SL, Rojas LZ. Influential factors in adherence to the therapeutic regime in hypertension and diabetes. Invest Educ Enferm. 2019;37(3):e02. Disponível em: https://doi.org/10.17533/udea.iee.v37n3e02
  » https://doi.org/10.17533/udea.iee.v37n3e02
• ²⁵ Muli S, Meisinger C, Heier M, et al. Prevalence, awareness, treatment, and control of hypertension in older people: results from the population-based KORA-age 1 study. BMC Public Health. 2020: 1049. Disponível em: https://doi.org/10.1186/s12889-020-09165-8
  » https://doi.org/10.1186/s12889-020-09165-8
• ²⁶ Francisco PMSB, Assumpção D de, Bacurau AG de M, Silva DSM da, Malta DC, Borim FSA. Multimorbidity and use of health services in the oldest old in Brazil. Rev bras epidemiol. 2021;24:e210014. Disponível em: https://doi.org/10.1590/1980-549720210014.supl.2
  » https://doi.org/10.1590/1980-549720210014.supl.2
• ²⁷ McMaughan DJ, Oloruntoba O, Smith ML. Socioeconomic Status and Access to Healthcare: Interrelated Drivers for Healthy Aging. Front Public Health. 2020; 8:231. Disponível em: https://doi.org/10.3389/fpubh.2020.00231
  » https://doi.org/10.3389/fpubh.2020.00231
• ²⁸ Yu ES, Hong K, Chun BC. Incidence and risk factors for progression from prehypertension to hypertension: a 12-year Korean Cohort Study. J Hypertens. 2020; 38:1755–1762. Disponível em: https://doi.org/ 10.1097/HJH.0000000000002494
  » https://doi.org/ 10.1097/HJH.0000000000002494
• ²⁹ Liu CW, Ke SR, Tseng GS, Wu YW, Hwang JJ. Elevated serum uric acid is associated with incident hypertension in the health according to various contemporary blood pressure guidelines. Nutr Metab Cardiovasc Dis. 2021;31(4):1209-1218. Disponível em: https://doi.org/10.1016/j.numecd.2021.01.003
  » https://doi.org/10.1016/j.numecd.2021.01.003
• ³⁰ Asgari S, Moazzeni SS, Azizi F, Abdi H, Khalili D, Hakemi MS, et al. Sex-Specific Incidence Rates and Risk Factors for Hypertension During 13 Years of Follow-up: The Tehran Lipid and Glucose Study. Glob Heart. 2020;15(1):29. Disponível em: https://doi.org/10.5334/gh.780
  » https://doi.org/10.5334/gh.780
• ³¹ Sun D, Zhou T, Heianza Y, Li X, Fan M, Fonseca VA, et al. Type 2 Diabetes and Hypertension. Circ Res. 2019;124(6):930-937. Disponível em: doi: https://doi.org/10.1161/CIRCRESAHA.118.314487
  » https://doi.org/10.1161/CIRCRESAHA.118.314487
• ³² Daugherty SL, Powers JD, Magid DJ, Tavel HM, Masoudi FA, Margolis KL. Incidence and prognosis of resistant hypertension in hypertensive patients. Circulation. 2012; 125:1635–1642. Disponível em: https://doi.org/10.1161/CIRCULATIONAHA.111.068064
  » https://doi.org/10.1161/CIRCULATIONAHA.111.068064
• ³³ Ku E, Lee BJ, Wei J, Weir MR. Hypertension in CKD: Core Curriculum 2019. Am J Kidney Dis. 2019;74(1):120-131. Disponível em: https://doi.org/ 10.1053/j.ajkd.2018.12.044
  » https://doi.org/ 10.1053/j.ajkd.2018.12.044
• ³⁴ García-Fabela L, Melano-Carranza E, Aguilar-Navarro S, García-Lara JM, Gutiérrez-Robledo LM, Avila-Funes JA. Hypertension as a risk factor for developing depressive symptoms among community-dwelling elders. Rev Invest Clín. 2009; 61:274–280. Disponível em: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4278846/
• ³⁵ Wang C, Yuan Y, Zheng M, Pan A, Wang M, Zhao M, et al. Association of Age of Onset of Hypertension With Cardiovascular Diseases and Mortality. J Am Coll Cardiol. 2020;75(23) 2921–2930. Disponível em: https://doi.org/10.1016/j.jacc.2020.04.038
  » https://doi.org/10.1016/j.jacc.2020.04.038

Edited by

• Edited by: Camila Alves dos Santos

Data availability

The datasets analyzed in the current study were used under license and are not publicly available due to the policies of the SABE Study.

Publication Dates

• Publication in this collection
  27 Jan 2025
• Date of issue
  2025

History

• Received
  03 June 2024
• Accepted
  15 Nov 2024