Prevalence of diabetic retinopathy in Pakistan: A systematic review

Methodological quality of the review: Low confidence

Author: Mumtaz SN, Fahim MF, Arslan M, Shaikh A, Kazi U, Memon MS

Region: Pakistan

Sector: Diabetic retinopathy

Sub-sector: Prevalence, Vision Threatening Diabetic Retinopathy

Equity focus:  None specified

Review type: Other review

Quantitative synthesis method: Narrative synthesis

Qualitative synthesis method: Not applicable

Background:

Pakistan, with a population of more than 200 million (recent census), is expected to have large number of diabetic patients with DR with no plan to combat the consequences. There is a lack of conclusive data highlighting problem of diabetes and DR to generate enough advocacy of the policy makers to plan a “National program” to address diabetes related blindness.

Objectives:

To review the literature on the prevalence of diabetic retinopathy (DR) and Vision threatening diabetic retinopathy (VTDR) in Pakistan.

Main findings:

Authors included a total of 29 studies in the review. All these studies were from three provinces, Sindh, Punjab and KPK. No study was reported from Baluchistan or Northern areas. All the studies excluding one were reported in eight different national journals. One study was published outside Pakistan in Turk J Med Sci. The majority of the studies (24 out of 29) were done in hospital setting, four studies were community based and only one study was mixed. The methodology of every study was dissimilar in terms of inclusion/exclusion criteria, and tools for DR detection.

In the included studies, pooled prevalence of DR was found to be 28.78% with a variation of 10.6% to 91.3%. Out of 29 studies, DR was classified in 19 studies. Pooled prevalence of VTDR in these 19 studies was found to be 28.2% (variation of 4% to 46.3%) of patient with retinopathy and 8.6% of all diabetics.

Authors concluded that a great variation in the values of DR and VTDR was observed in this study. Researchers suggest a community-based study with uniform methodology to find out a comparable value of prevalence of DR and VTDR in all provinces of Pakistan.

Methodology: 

Authors conducted a search on the following electronic databases Medline, Pub Med and Google scholar using search key words, ‘diabetic retinopathy’, ‘frequency/prevalence’ and ‘Pakistan’. Inclusion criteria consisted of population-based and hospital-based studies conducted in Pakistan during 1990 and March 2017, written in English.

All selected studies were reviewed by the following criteria: setting of retinal screening, tools used for retinal screening, human resources involved in retinal screening and classification or grading of DR.

Authors used a statistical package to analyse the data. Frequencies and percentages were calculated for quantitative variable.

Applicability/external validity:

Findings are applicable to Pakistan only, as authors only included population-based or hospital-based studies conducted in Pakistan.

Geographic focus:

Authors focused on prevalence studies conducted in Pakistan.

Summary of quality assessment:

Low confidence was attributed as important limitations were identified within the review. Authors did not conduct a thorough search of the literature to ensure that all relevant studies were included in the review. In addition, it is not clear from the review if authors used appropriate methods to screen studies for inclusion and extract data of included studies. Authors did not report appraising the quality or risk of bias of studies, therefore it is not clear which evidence is subject to high or low risk of bias.