Abstract
Noncommunicable diseases and related risk factors are the leading causes of disease burden in Iran and other middle-income countries. High blood pressure caused 80,000 deaths in Iran in 2005, and hyperglycemia caused 34,000 deaths in that year. A new study suggests that the Iranian primary health-care system, if provided with enough trained health workers and well-defined guidelines, can effectively reduce chronic disorders such as diabetes and hypertension, particularly in rural areas.
The study, “Effectiveness of diabetes and hypertension management by rural primary health-care workers (Behvarz workers) in Iran: a nationally representative observational study,” is by researchers at IHME, Harvard School of Public Health, the Iranian Ministry of Health and Medical Education, Tehran University of Medical Sciences, Shahid Beheshti University of Medical Sciences, and Imperial College, London.
Research objective
While cardiovascular diseases have decreased in high-income countries, in part because of lifestyle changes such as reducing smoking, high blood pressure, and cholesterol, these risk factors have increased or remained unchanged in many low- and middle-income countries such as Iran. In places with limited numbers of physicians and health facilities, primary health-care workers might provide a cost-effective way to manage risk factors for noncommunicable diseases.
However, few studies have examined the question, and this lack of evidence hinders the development of policies for controlling noncommunicable diseases, which were identified as a major global health priority at the 2011 High-level Meeting of the United Nations.
The researchers set out to examine the effectiveness of the Iranian rural primary health-care system, the Behvarz system of community health workers, in the management of diabetes and hypertension, the two leading metabolic risk factors for mortality in Iran. They also wanted to determine whether a higher density of Behvarz workers is associated with improved outcomes at the district level.
Research findings
Nationally, 39.2% of individuals with diabetes and 35.7% of those with hypertension received treatment. Coverage was higher for women than men and in urban areas than in rural areas. Prevalence of both diseases was higher in women than in men. While diabetes prevalence was higher in urban areas than in rural areas, treatment of diabetes in Iran was more effective in rural areas. In contrast, the difference in prevalence between urban and rural areas for hypertension was very small, though urban residents had slightly better results in terms of treatment.
Treatment of individuals with diabetes lowered mean fasting plasma glucose by an estimated 1.34 mmol/L in rural areas and 0.21 mmol/L in urban areas. The systolic blood pressure of urban individuals treated for hypertension was 3.8 mm Hg lower than it would have been if there was no treatment. In rural areas treatment lowered systolic blood pressure by 2.5 mm Hg. In all areas, there was strong correlation of higher age and body mass index with higher fasting plasma glucose and systolic blood pressure.
The likely reason for the difference in effectiveness of treatment for diabetes versus blood pressure is that Behvarz community health workers have a specific role in Iran’s national diabetes control program. Concentrated most heavily in poorer districts, Behvarz workers are educated to identify individuals at high risk for diabetes, refer them to physicians at local “health houses” for testing, and follow up with treatment and lifestyle guidance. No specific training program is in place for Behvarz workers to manage high blood pressure.
An increase of one Behvarz worker per 1,000 residents was associated with a 0.09 mmol/L reduction in fasting blood glucose. The association of Behvarz worker density with change in systolic blood pressure was too small to have relevance to public health policy. The researchers found no association in rural areas between the number of physicians and treatment effects for diabetes.
The difference in diabetes treatment effects of Behvarz workers versus physicians can be attributed to the fact that Behvarz workers regularly follow up with diet and lifestyle education and check patients’ adherence to treatment.
Analytical approach
The researchers used a nationally representative sampling from the 2005 Non-Communicable Disease Surveillance Survey to measure the coverage of treatment for diabetes and hypertension and to estimate the effectiveness of treatment. Censuses provided socioeconomic information and the number of Behvarz workers by areas. The study used data for nearly 66,000 participants; of those almost 12,000 lived in rural areas.
The researchers took two distinct statistical approaches to control for potential confounding in different ways: a mixed-effects regression analysis, adjusted for socioeconomic and other covariates, and an estimate of treatment effect balanced with propensity score matching based on individual and community characteristics.
Policy implications
The Iranian primary health-care system has several challenges. Despite the system’s progress in preventing and controlling diabetes, increased efforts are needed to diagnose diabetes and other noncommunicable diseases and risk factors. The approach of using Behvarz workers could provide a model for how primary care can manage chronic diseases.
The study also suggests that a national program with well-developed guidelines should be implemented to improve the primary health-care system’s focus on lowering high blood pressure. The study’s findings support the feasibility of managing noncommunicable diseases, especially in rural areas, through the use of trained community health-care personnel, an approach that could be more cost effective than training more physicians.
FUNDING
Bill & Melinda Gates Foundation – Disease Control Priorities Network (Investment # OPP51229)
