Table 2.
Effect of any stressful life events after onset of psychosis on number and length of subsequent relapses as indexed by hospital admission
|
Number of relapses (n=253) |
Number of relapses (with medication adherence; n=240) |
Length of relapses (n=253) |
Length of relapses (with medication adherence; n=240) |
||||||
|---|---|---|---|---|---|---|---|---|---|
| IRR (95% CI) | p value | IRR (95% CI) | p value | IRR (95% CI) | p value | IRR (95% CI) | p value | ||
| Any stressful life events before first relapse | |||||||||
| No | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | |
| Yes | 1·87 (1·24–2·80) | 0·0026 | 1·81 (1·15–2·82) | 0·010 | 2·53 (1·40–4·67) | 0·0011 | 2·30 (1·26–4·32) | 0·0045 | |
| Age of onset, years* | |||||||||
| <22 | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | |
| 22 to <25 | 0·94 (0·74–1·22) | 0·66 | 0·94 (0·72–1·24) | 0·66 | 0·93 (0·64–1·35) | 0·69 | 1·03 (0·70–1·51) | 0·86 | |
| 25 to <30 | 1·18 (0·02–55·0) | 0·93 | 0·76 (0·01–40·7) | 0·89 | 0·87 (0·00–259) | 0·96 | 0·24 (0·00–77·8) | 0·60 | |
| 30 to <39 | 0·79 (0·00–19 437) | 0·96 | 3·20 (0·00–123 453) | 0·83 | 1·58 (0·00–4 302 739) | 0·95 | 40·3 (0·00–150 049 840) | 0·59 | |
| ≥39 | 1·10 (0·00–3565) | 0·98 | 0·29 (0·00–1273) | 0·77 | 0·78 (0·00–112 259) | 0·96 | 0·06 (0·00–10 706) | 0·62 | |
| Sex | |||||||||
| Female | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | |
| Male | 0·84 (0·57–1·25) | 0·39 | 0·75 (0·50–1·12) | 0·15 | 1·18 (0·67–2·07) | 0·53 | 1·10 (0·62–1·93) | 0·72 | |
| Ethnicity | |||||||||
| White | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | |
| Asian | 1·51 (0·57–3·55) | 0·37 | 0·95 (0·31–2·48) | 0·93 | 1·86 (0·55–6·34) | 0·28 | 1·34 (0·38–4·72) | 0·63 | |
| Black African or Caribbean | 1·89 (1·17–3·16) | 0·012 | 1·63 (0·99–2·75) | 0·063 | 2·55 (1·37–4·83) | 0·0031 | 2·37 (1·27–4·47) | 0·0069 | |
| Mixed | 2·05 (0·94–4·23) | 0·060 | 1·78 (0·80–3·75) | 0·14 | 2·28 (0·76–7·20) | 0·12 | 2·03 (0·67–6·39) | 0·18 | |
| Cannabis use | |||||||||
| Former | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | |
| Never | 1·35 (0·72–2·62) | 0·36 | 1·58 (0·82–3·15) | 0·18 | 1·45 (0·63–3·38) | 0·38 | 1·94 (0·81–4·79) | 0·13 | |
| Intermittent | 1·05 (0·52–2·10) | 0·90 | 1·11 (0·53–2·29) | 0·78 | 2·31 (0·98–5·57) | 0·048 | 2·69 (1·09–6·83) | 0·024 | |
| Continued hash-type | 1·19 (0·41–3·03) | 0·73 | 1·18 (0·40–3·09) | 0·75 | 0·84 (0·20–3·69) | 0·81 | 0·81 (0·19–3·51) | 0·77 | |
| Continued regular skunk-type | 1·04 (0·46–2·29) | 0·92 | 1·00 (0·44–2·21) | >0·99 | 1·51 (0·52–4·52) | 0·41 | 1·45 (0·50–4·34) | 0·47 | |
| Continued heavy skunk-type | 1·64 (0·86–3·19) | 0·14 | 1·45 (0·73–2·93) | 0·29 | 2·08 (0·82–5·38) | 0·10 | 2·31 (0·89–6·17) | 0·063 | |
| Other drug use | |||||||||
| Non-use | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | |
| Experimental | 0·74 (0·31–1·56) | 0·46 | 0·57 (0·21–1·32) | 0·23 | 1·48 (0·56–4·04) | 0·42 | 1·43 (0·54–3·92) | 0·47 | |
| Regular | 1·91 (1·06–3·40) | 0·029 | 1·82 (0·99–3·28) | 0·050 | 2·29 (0·95–5·65) | 0·051 | 2·28 (0·96–5·58) | 0·052 | |
| Nicotine use | |||||||||
| Non-use | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | |
| Intermittent | 1·95 (0·85–4·16) | 0·095 | 2·39 (1·04–5·15) | 0·032 | 2·45 (0·93–6·66) | 0·066 | 3·25 (1·23–8·85) | 0·017 | |
| Continued | 2·00 (1·21–3·31) | 0·0069 | 2·33 (1·37–3·99) | 0·0019 | 2·00 (1·05–3·84) | 0·032 | 2·56 (1·34–4·98) | 0·0045 | |
| Alcohol use | |||||||||
| No use | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | |
| Continued | 1·26 (0·72–2·12) | 0·40 | 1·51 (0·83–2·65) | 0·16 | 1·03 (0·48–2·23) | 0·94 | 1·19 (0·56–2·57) | 0·65 | |
| Care intensity at onset | |||||||||
| Community mental health team | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | |
| Crisis team | 0·99 (0·30–2·98) | 0·99 | 0·87 (0·25–2·72) | 0·82 | 0·92 (0·21–3·83) | 0·90 | 0·82 (0·18–3·58) | 0·79 | |
| Non-compulsory admission | 2·15 (1·08–4·79) | 0·042 | 1·88 (0·93–4·22) | 0·10 | 2·29 (0·89–6·19) | 0·071 | 2·20 (0·86–5·93) | 0·091 | |
| Compulsory admission | 2·26 (1·18–4·90) | 0·024 | 2·09 (1·07–4·58) | 0·045 | 4·30 (1·79–10·9) | 0·0007 | 4·76 (1·98–12·2) | 0·0003 | |
| Relationship status | |||||||||
| In relationship | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | |
| Not in relationship | 1·33 (0·87–2·09) | 0·20 | 1·58 (1·00–2·58) | 0·057 | 2·52 (1·36–4·74) | 0·0025 | 3·29 (1·71–6·47) | 0·0003 | |
| Psychosis diagnosis | |||||||||
| Non-affective | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | 1 (ref) | .. | |
| Affective | 0·74 (0·42–1·23) | 0·27 | 0·91 (0·51–1·56) | 0·75 | 0·48 (0·22–1·03) | 0·044 | 0·55 (0·25–1·21) | 0·11 | |
| Medication adherence | |||||||||
| Regular compliance | .. | .. | 1 (ref) | .. | .. | .. | 1 (ref) | .. | |
| Irregular compliance | .. | .. | 1·84 (1·17–2·95) | 0·010 | .. | .. | 1·63 (0·91–2·94) | 0·083 | |
| Poor compliance | .. | .. | 3·30 (1·85–5·90) | <0·0001 | .. | .. | 2·66 (1·22–5·97) | 0·0094 | |
IRRs included adjustment for sociodemographic factors (sex, ethnicity, and relationship status) and clinical factors (psychosis diagnosis, intensity of care at onset, and alcohol, nicotine, and other drug use; with analysis stratified by cannabis use). Where indicated, the model also adjusted for medication adherence. IRR=incidence rate ratio.
*
Age of onset was modelled as a restricted cubic spline function with knots placed at ages of onset of 22 years, 25 years, 30 years, and 39 years.