Comparing incidence of vasculitis between farming, rural and urban population: A population-based study

Vasculitis often poses a significant burden on individuals, their families and the health care system. Understanding its epidemiology can aid in facilitating timely interventions. We present a province-wide population study comparing the 1) incidence of vasculitis amongst farmers, rural-non farmers and urban residents, 2) the use of health services and 3) all-cause mortality rates across the three cohorts.

The groups were randomly selected on the basis of provincial health data. Criteria for ascertaining vasculitis cases included either one hospital admission, two physician visits within a 2-year interval, or two ambulatory care visits within 2 years related to the vasculitis diagnosis. Descriptive statistics were used to compare the incidence rates.

A total sample size of 302,089, with 5437 vasculitis cases. Farmers had the highest incidence of all types of vasculitis (109.8/100,000 person-years (PY)), followed by rural non-farmers (93.1/100,000 PY) and urbanites (71.7/100,000 PY). Age at diagnosis was higher among farmers (66.2 years) compared to rural non-farmers (64.5 years) and urbanites (63.9 years). Polymyalgia rheumatica (PMR) accounted for 47% of cases, followed by Arteritis Unspecified (15%) and small-vessel vasculitis (14%). Within the farming population, a higher percentage of males had positive cases of vasculitis compared to other populations. Rural non-farmer population had the highest use of health care services and unadjusted non-injury mortality rate (31.8/100,000 PY), followed by rural farmers (25.4/100,000 PY) and urban residents (23.8/100,000 PY).

Our province-wide study revealed that farmers face the highest incidence rates of vasculitis as well as the second highest burden of disease in terms of healthcare service needs and mortality. Key PointsAQ • There is a notable variation in the incidence rates of vasculitis among farmers, rural and urban residents with the farming population showing the highest incidence rate across most subtypes of vasculitis. • Farmers had a greater percentage of males diagnosed with vasculitis and an older age at diagnosis. • Rural non-farming patients with vasculitis demonstrate the highest utilization of healthcare services and mortality.