Table 2.
Symptom-cluster at baseline | Individually-evaluated effecta | Mutually-adjusted effectb | ||
---|---|---|---|---|
HR | P-value | HR | P-value | |
(95% CI) | (95% CI) | |||
Presence of Hyperactivity symptoms | 1.3 (1.1–1.5) | <0.001 | 1.1 (0.9–1.3) | 0.364 |
Presence of Affective symptoms | 1.7 (1.5–2.0) | <0.001 | 1.6 (1.4–1.9) | <0.001 |
Presence of Psychotic symptoms | 1.8 (1.3–2.5) | <0.001 | 1.6 (1.2–2.2) | 0.004 |
HR, hazard ratio; CI, confidence interval.
Only one symptom-cluster was included in the model at a time. In other words, three separate models of cox regression were evaluated, each including only one of the symptom-clusters (either Hyperactivity, Affective or Psychotic symptoms). The models also adjusted for baseline covariates of age, sex, ethnicity, years of education, first-degree family member with cognitive impairment, Mini-Mental State Examination score, subtypes of mild cognitive impairment, recruitment sites, year of recruitment, and whether the diagnosis was made via consensus conference.
The three symptom-clusters were concurrently included in the model to evaluate their mutually-adjusted effects. In other words, a cox regression was conducted by including the three symptom-clusters, as well as adjusting for the baseline confounders (age, sex, ethnicity, years of education, first-degree family member with cognitive impairment, Mini-Mental State Examination score, subtypes of mild cognitive impairment, recruitment sites, year of recruitment, and whether the diagnosis was made via consensus conference).