Table 3 Meta-analysis results
Arial | 8 | Study type(s) | Total included studies | Total participants | Effect size type | Effect size (95% CI) | p | I2 | Small study effect | Excess significance bias | PI | Level of evidence |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Mortality | All-cause mortality | Cohort | 18 | 19,813 | RR | 2.37 (2.02–2.78) |  < 1–6 | 42.31 | Yes | No | 1.50–3.73 | Grade II |
CVD mortality in all DR | 10 | 11,239 | RR | 1.83 (1.42–2.36) |  < 1–6 | 76.28 | No | Yes | 0.81–4.13 | Grade II | ||
CVD mortality in mild DR | 4 | 7,361 | RR | 1.14 (0.81–1.58) | 0.45 | 63.24 | No | NS | 0.30–4.29 | NS | ||
CVD mortality in severe DR | 6 | 9,691 | RR | 2.26 (1.31–3.91) |  < 1–6 | 84.96 | No | No | 0.37–13.8 | Grade II | ||
Disease | Obstructive sleep apnoea | Case–control | 6 | 1,092 | OR | 2.16 (1.35–3.44) | 0.001 | 52.12 | No | No | 0.57–8.74 | Grade II |
Chronic kidney disease | Cohort | 2 | 781 | OR | 2.73 (0.37–19.95) | 0.32 | 97.22 | No | NS | NA | NS | |
Non-alcoholic fatty liver disease all DR | Cross-sectional | 8 | 7,170 | OR | 1.00 (0.48–2.10) | 1.00 | 96.65 | Yes | NS | 0.07–14.9 | NS | |
Non-alcoholic fatty liver disease non-proliferative DR | 3 | 3,977 | OR | 0.74 (0.37–1.50) | 0.40 | 95.25 | No | NS | 0.00–5561.39 | NS | ||
Non-alcoholic fatty liver disease proliferative DR | 3 | 3,977 | OR | 0.96 (0.21–4.28) | 0.96 | 96.53 | No | NS | 0.00–162,240,006.20 | NS | ||
Primary open angle glaucoma | Cohort | 2 | 241,037 | OR | 1.47 (0.57–3.77) | 0.42 | 95.45 | No | NS | NA | NS | |
Cross-sectional | 4 | 15,389 | OR | 1.01 (0.56–1.81) | 0.98 | 84.32 | No | NS | 0.07–14.14 | NS | ||
Mental Health | Depression (Type I)†| Case–control | 3 | 971 | OR | 2.19 (0.91–5.24) | 0.08 | 84.99 | Yes | NS | 0.00–86,679.18 | NS |
Depression (Type 2) †| Cross-sectional | 9 | 31,766 | OR | 1.62 (1.37–1.91) |  < 1–6 | 43.36 | No | Yes | 1.09–2.41 | Grade II | |
Eating disorders | Cross-sectional | 7 | 1,091 | OR | 2.81 (1.67–4.72) |  < 1–6 | 35.21 | No | No | 0.82–9.63 | Grade II | |
Alzheimer’s | Cohort | 2 | 46,185 | OR | 1.56 (1.16–2.08) | 0.003 | 0.00 | Yes | No | NA | Grade IV | |
Dementia | Cohort | 3 | 7,754 | OR | 1.46 (1.09–1.94) | 0.01 | 73.64 | No | No | 0.05–39.66 | Grade IV | |
Cognitive impairment | Cross-sectional | 5 | 2,451 | OR | 2.07 (1.11–3.88) | 0.02 | 60.03 | No | No | 0.28–15.06 | Grade IV | |
Cohort | 5 | 1,397 | OR | 2.71 (1.90–3.87) |  < 1–6 | 0.02 | Yes | No | 1.90–3.87 | Grade II |