Geographic and socio-demographic differences in uptake of population-based screening for atrial fibrillation: The STROKESTOP I study

BackgroundThe rationale behind screening for atrial fibrillation (AF) is to prevent ischemic stroke. Socio-demographic differences are expected to affect screening uptake. Geographic differences may provide further insights leading to targeted interventions for improved uptake. The objective of this study was to evaluate geographic and socio-demographic differences in uptake of AF screening in the population-based study STROKESTOP I.MethodsSTROKESTOP was carried out in two Swedish counties with a total population of 2.3 million inhabitants. Half of the residents aged 75-76 years were randomized to the screening arm: invitation to clinical examination followed by ambulant ECG recording. Information on each invited person's residential parish (n = 157) was used. On parish-level, aggregated data for the participants and non-participants, respectively, were obtained with respect to socioeconomic variables: educational level, disposable income, immigrant and marital status. Geo-maps displaying participation ratios were estimated by hierarchical Bayes methods.ResultsThe overall participation rate was similar in men and women but lower in Stockholm, 47.6% (5665/11,903) than in Halland, 61.2% (1495/2443). Participation was clearly associated with the socioeconomic variables. Participation not taking into account socioeconomy varied more markedly across the parishes in the Stockholm county (range: 0.65-1.26) than in the Halland county (0.94-1.27). After adjustment for socioeconomic variables, a geographic variation remained in Stockholm, but not in Halland.ConclusionParticipation in AF screening varied according to socioeconomic conditions. Geographic variation in participation was marked in the Stockholm county, with only one screening clinic. Geo-mapping of participation yielded useful information needed to intervene for improved screening uptake.