Retinopathy in patients with hypertension and / or diabetes in a family health unit

1 Faculdade de Medicina e Cirurgia do Pará – Universidade Federal do Pará (UFPA) – Belém (PA), Brasil; 2 Clínica Oftalmológica da Universidade Federal de Minas Gerais (UFMG); Faculdade de Medicina e Cirurgia do Pará (UFPA) – Belém (PA), Brasil; 3 Universidade Federal do Amazonas (UFAM) – Manaus (AM), Brasil; Universidade Federal do Pará, Faculdade de Medicina e Cirurgia do Pará; Hospital Universitário Bettina Ferro de Souza – Belém (PA), Brasil.


INTRODUCTION
H ypertension and diabetes mellitus (DM) are the major risk factors for cardiovascular disease and have been the leading cause of death in Brazil in recent decades (1,2) . These are chronic conditions that result in high costs with hospitalisations and complex procedures for the treatment of long-term complications (3) .
Diabetic retinopathy (DR) is one of the microvascular complications of diabetes, particularly in long-term diabetes with poor glycemic control. It is estimated that 99% of patients with type 1 DM and 60% of patients with type 2 DM suffer from some type of DR after 20 years with the disease, making it the main cause of acquired blindness in adults (4)(5)(6) .
Hypertensive retinopathy (HR) is characterised as a spectrum of vascular changes in the retina of individuals with high blood pressure. Screening patients for the condition is critical as it is an indication for drug therapy, even in patients with stage 1 hypertension, because of its association with increased cardiovascular risk (7) .
The Brazilian Ministry of Health has implemented the Reorganisation Plan for Hypertension and Diabetes Mellitus Care as a strategy to reorganise primary care. The programme involves collecting data on these patients in a national database called HIPERDIA (1) . Therefore, primary-care physicians are essential to minimise the long-term complications of these conditions. Training physicians and providing ophthalmoscopes to family health clinics would increase the number of patients referred to timely specialised care, allowing early diagnosis of retinopathy and better treatment outcomes.

METHODS
Individual, observational, primarily descriptive crosssectional study. The study sample was a cohort of 50 patients with hypertension and/or diabetes seen at a Family Health Unit (FHU) in the municipality of Ananindeua, Pará, and included in the HIPERDIA database. Patients who sought the FHU for medical or nursing consultations between September and November 2009 were included in the study through nonprobabilistic convenience sampling.
Data collection was done weekly in the FHU through a questionnaire applied in a private room, measurement of blood pressure, and ophthalmoscopy with pupillary dilation by tropicamide and phenylephrine.
Patients with significant changes on fundus examination were referred for ophthalmic evaluation at the University Hospital Bettina Ferro de Souza (HUBFS), where they underwent retinography and specific treatment where appropriate.
Qualitative and quantitative statistical analysis was done using the EpiInfo 3.5.1 software. Uni-and bivariate analysis was conducted using the chi-square test with Yates correction, where applicable, and Fisher's exact test, with a significance level of 5% and a 95% confidence interval (95% CI).
Statistical analysis of ophthalmoscopic changes was done in two stages: one in which all changes were considered (where p = p 1 ), and another excluding the findings of arteriolar narrowing or mild vein engorgement (specific analysis where p = p 2 ), as these findings can also be related to other factors such as old age and arteriosclerotic retinopathy.

DISCUSSION
The study population was similar to previous studies in the literature, with a predominance of females (8)(9)(10) . It is worth noting the association between female patients and changes on fundus examination, which could mean that women have a higher chance of receiving a diagnose because they seek medical care more often.
On average, patients attended 6 (±4.36) medical visits per year, which was significantly associated with changes on ophthalmoscopy (p 1 =0.03, p 2 =0.0002). This result might indicate that individuals who attend medical visits less frequently may have higher chances of developing retinopathy.
This study showed that patients were not undergoing regular preventive ophthalmic care, as they had attended their last ophthalmic visit on average 2.44±2.38 years (p 1 =0.03, p 2 =0.04) earlier, and 14% reported that they had never visited an ophthalmologist, which is consistent with the literature (11) .
The average last reported fasting plasma glucose was high (164.32±111.04 mg/dl), with values as high as 491mg/dl, also similar to results found in the literature (10,11) .
Mean SBP was 142±21.76 mmHg and mean DBP was 82±12.77 mmHg. A DBP above 90 mmHg was significantly associated with changes on fundus examination (p 2 =0.009). Chronic vascular damage caused by high blood pressure is known to be one of the main systemic complications of long-term hypertension and is often complicated by concomitant DM (7,10,13,14) .
Chronic diseases such as hypertension and DM require continuous patient motivation to ensure adherence to treatment. This is why a multidisciplinary approach is essential for adequate metabolic control in order to prevent chronic complications (7,13) . In total, 64% of patients reported that they were on some type of diet, and failing to follow a diet was significantly associated with changes on fundus examination (p 2 =0.009).
The prevalence of abnormal findings on fundus examination was 58.7% when all changes were considered and 39.1% when arteriolar narrowing or mild venous engorgement were excluded, demonstrating the importance of early screening of retinal changes in a population under high risk for cardiovascular disease such as the one studied here. The presence of specific findings on fundus examination was more frequent among patients with both DM and hypertension (45.5%), which might indicate the synergistic action of the two conditions in damaging the retina (15,16) .
General practitioners and endocrinologists should be well informed about the diagnosis and treatment of retinopathy due to its significant social and economic impact. However, in a study (17) where physicians were asked about the correct indications for ophthalmoscopy, it was correctly indicated to 86.9% of patients with type 2 DM and only 36.9% of patients with type 1 DM (p<0.001), especially among physicians who had graduated less than 5 years earlier (p<0.003). The study also showed that most respondents (52.4%) had had some experience with fundus examination during their medical studies, but only 24% actually performed it on their patients.
Another study (18) that compared the agreement between trained family physicians and ophthalmologists in their diagnoses made by retinography suggests that, after receiving training, family physicians would be able to assess retinographies, thus confirming their important role in the integral health of patients and consolidating the importance of fundus examination as a diagnostic method in primary care. Similar results can be found in the literature (19,20) .

CONCLUSION
The high prevalence of ophthalmoscopic changes found in this study indicates the importance of primary care in the prevention of hypertensive and diabetic retinopathy. Prevention should be based in the active search for new cases, proper use of available tools such as the HIPERDIA database to plan health surveillance, and multidisciplinary management of patients aimed at strict metabolic control to avoid micro-and macrovascular complications.
Monocular direct ophthalmoscopy is a relatively simple, low-cost, and therefore accessible test that can be offered to the most deprived populations. It is an important screening and monitoring tool for patients with hypertension or diabetes, giving general practitioners more control over the clinical course of their patients and, crucially, leading to more accurate referrals of patients to ophthalmologists. This policy results in lower costs for the healthcare system as well as improved patient assessment and treatment, with better long-term outcomes and a lower disease burden. However, measures to implement ophthalmoscopy as a routine test in outpatient clinics are still incipient and do not meet population demands.