Abstract
The Hajj mass gathering is attended by over two million Muslims each year, many of whom are elderly and have underlying health conditions. Data on the number of pilgrims with health conditions would assist public health planning and improve health services delivery at the event. We carried out a systematic review of literature based on structured search in the MEDLINE/PubMed, SCOPUS and CINAHL databases, and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, to estimate the prevalence of diabetes and hypertension among Hajj pilgrims. Twenty-six studies conducted between 1993 and 2018 with a total of 285,467 participants were included in the review. The weighted pooled prevalence rates of hypertension and diabetes among Hajj pilgrims in all included studies were 12.2% (95% CI: 12.0-12.3) and 5.0% (95% CI: 4.9-5.1), respectively. The reported prevalence of other underlying health conditions such as chronic respiratory, kidney or liver disease, cardiovascular disease, cancer and immune deficiency were generally low. Potentially a large number of pilgrims each Hajj have diabetes and/or hypertension and other underlying health conditions. Hajj could be a great opportunity to reduce the burden of these diseases within the over 180 countries participating in the event by identifying undiagnosed cases and optimizing patients' knowledge and management of their conditions. Prospero registration number: CRD42020171082.