Total mortality

All nine studies reported on total mortality, with follow-up ranging from five to 30 years (21,23,24,29,31,32,38,41,42). All reported no reduction in total mortality following screening for CVD risk and CVD risk factors. This finding was confirmed by the meta-analysis, which determined an overall relative risk for total mortality of 1.00 (95% CI: 0.97–1.03; Table A5.1).

Table A5.1.

Screening for CVD risk/risk factors: meta-analysis of total mortality outcomes.

A low level of heterogeneity across all nine studies indicated that they had produced similar results. Sensitivity analyses of the risk of bias did not alter the overall results, confirming that the analysis was robust. The inclusion of adjusted results (hazard ratios) instead of the absolute number of cases did not change the results.

CVD morbidity and mortality

The two studies that reported on CVD morbidity and mortality (combined) had follow-up periods of 10 and 24 years (21,24). Both reported no reductions in CVD morbidity and mortality following screening for CVD risk and CVD risk factors. This finding was confirmed in the meta-analysis, which determined an overall relative risk for CVD morbidity and mortality of 1.02 (95% CI: 0.95–1.10; Table A5.2).

Table A5.2.

Screening for CVD risk/risk factors: meta-analysis of CVD morbidity and mortality.

A low level of heterogeneity across the two studies indicated that they had produced similar results. Sensitivity analyses of the risk of bias did not alter the overall effect estimate, which strengthened confidence in the meta-analysis.

CVD mortality

The five studies that reported on CVD mortality had follow-up ranging from five to 22 years (29,31,38,41,42). The study with the shortest follow-up reported a reduction in CVD mortality among participants in the screened group after five years (38). The other four studies reported no reductions in CVD mortality (29,31,41,42). The latter finding was confirmed in the meta-analysis, which determined an overall relative risk of CVD mortality of 1.04 (95% CI: 0.73–1.49; Table A5.3).

Table A5.3.

Screening for CVD risk/risk factors: meta-analysis of CVD mortality.

Substantial heterogeneity across the studies indicated that they had not produced similar results. Sensitivity analyses of the risk of bias did not alter the overall effect estimate, which strengthened confidence in the meta-analysis.

IHD morbidity and mortality

A total of four studies reported on IHD morbidity and mortality (combined) (21,23,29,32), with follow-up ranging from around nine to 30 years. All four studies reported no reduction in IHD morbidity and mortality following screening for CVD risk and CVD risk factors. This finding was confirmed by the meta-analysis, which determined an overall relative risk for IHD morbidity and mortality of 1.00 (95% CI: 0.96–1.05; Table A5.4).

Table A5.4.

Screening for CVD risk/risk factors: meta-analysis of IHD morbidity and mortality.

A low level of heterogeneity across all four studies indicated that they had produced similar results. Sensitivity analyses of the risk of bias did not alter the overall results, which strengthened confidence in the meta-analysis.

IHD mortality

In all, two studies reported outcomes for IHD mortality, with follow-up ranging from 9 to 11.8 years (29,32). Both studies reported no reductions in IHD mortality following screening for CVD risk and CVD risk factors. This finding was confirmed in the meta-analysis, which determined an overall relative risk for IHD mortality of 1.00 (95% CI: 0.90–1.12; Table A5.5).

Table A5.5.

Screening for CVD risk/risk factors: meta-analysis of IHD mortality.

A low level of heterogeneity across both studies indicated that they had produced similar results. Sensitivity analyses of the risk of bias did not alter the overall effect estimate, which strengthened confidence in the meta-analysis.

Stroke morbidity and mortality

Three studies reported on stroke morbidity and mortality (combined) (21,23,32). Two studies, with follow-up of 10 and 11.8 years, reported no reductions in this outcome following screening for CVD risk and CVD risk factors (21,32). The third study, which had follow-up of around 30 years, reported an increased risk of stroke in the screened group (23). The meta-analysis found an overall relative risk for stroke morbidity and mortality of 1.05 (95% CI: 0.95–1.17), indicating no difference in the risk of stroke following screening for CVD risk and CVD risk factors (Table A5.6).

Table A5.6.

Screening for CVD risk/risk factors: meta-analysis of stroke morbidity and mortality.

Moderate heterogeneity across all three studies indicated that they had not produced similar results. Sensitivity analyses of the risk of bias did not alter the overall effect estimate, which strengthened confidence in the meta-analysis.

Stroke mortality

Only one study reported on screening for CVD risk and CVD risk factors. It found that screening did not lead to a reduction in stroke mortality after 11.8 years of follow-up (32).

Total mortality

All four studies reported total mortality for men, with follow-up ranging from 10 to 15 years (45,48–50). None of the studies reported a reduction in total mortality following screening. This finding was confirmed in the meta-analysis, which determined an overall relative risk for total mortality of 0.99 (95% CI: 0.98–1.00; Table A5.7). Only one study reported total mortality for women: it found no reduction at five years after screening (46).

Table A5.7.

Screening for AAA: meta-analysis of total mortality.

A low level of heterogeneity across studies indicated that they had produced similar results. Sensitivity analyses of the risk of bias did not alter the overall effect estimate, which strengthened confidence in the meta-analysis. However, the inclusion of adjusted results (hazard ratios) instead of the absolute number of cases showed a 2% reduction in total mortality (relative risk: 0.98; 95% CI: 0.96–0.99; Table A5.8).

Table A5.8.

Screening for AAA: meta-analysis of AAA mortality.

AAA mortality

All four RCTs reported AAA mortality for men, with follow-up ranging from 10 to 15 years (45,48–50). Two of the studies reported reductions in AAA mortality following screening (48,49), whereas the other two reported no reductions (45,50). The meta-analysis showed that screening reduces AAA mortality, with an overall relative risk of 0.63 (95% CI: 0.41–0.97; Table A5.1). The only identified study to report findings for women found no reduction in AAA mortality at five years after screening (46).

Substantial heterogeneity across studies indicated that they had not produced similar results. Sensitivity analyses of the risk of bias did not alter the overall effect estimate, which strengthened confidence in the meta-analysis. Furthermore, the inclusion of adjusted results (hazard ratios) instead of the absolute number of cases did not change the results.

AAA rupture

Two studies reported AAA rupture for men (45,48): one study reported no reduction in AAA rupture after 15 years (45), whereas the other reported a relative risk reduction of almost 50% in the screened group after 10 years (48). The meta-analysis showed that screening does not reduce AAA rupture, with an overall relative risk of 0.66 (95% CI: 0.40–1.09). The only identified study to report findings for women found no reduction in the AAA rupture rate at five and 10 years after screening (47).

Substantial heterogeneity across studies indicated that they had not produced similar results. Sensitivity analyses of the risk of bias did not alter the overall effect estimate, which strengthened confidence in the meta-analysis. Furthermore, the inclusion of adjusted results (hazard ratios) instead of the absolute number of cases did not change the results.

Table A5.9.

Screening for AAA: meta-analysis of AAA rupture.