Difference in the prevalence of non-fatal suicidal behaviours in patients with unipolar and bipolar depression in China: a meta-analysis

Difference in the prevalence of non-fatal suicidal behaviours in patients with unipolar and bipolar depression in China is rarely reported. We conducted a meta-analysis to examine this difference. Major Chinese and English literature databases were searched online to collect studies comparing the prevalence of non-fatal suicidal behaviours of patients with unipolar and bipolar depression. The quality of the included studies was assessed according to the matching principle. Risk difference (RD) of prevalence rates of non-fatal suicidal behaviours between patients with unipolar and bipolar depression was calculated. A total of 16 studies, containing 1678 cases with unipolar depression and 1069 cases with bipolar depression, were included. Differences in rates of suicidal ideation and attempt were not statistically significant between patients with unipolar and bipolar depression, but rates of overall non-fatal suicidal behaviours in patients with unipolar depression was significantly higher than those with bipolar depression (RD: 0.28, 95% CI: 0.20, 0.36). In summary, the rate of overall non-fatal suicidal behaviours of patients with unipolar depression is higher than that of patients with bipolar depression in China.