6–9.8 mg/day), galantamine (8–24 mg/day), or memantine (10–20 mg/day), or a combination of these cognitive enhancers. Cognitive outcomes were routinely assessed during each clinic visit using the MMSE, Montreal Cognitive Assessment (MoCA), and Geriatric Depression Scale (GDS) [23, 24]. MMSE and MoCA were used as the selleckchem primary outcomes
of this study. These endpoints were used to estimate the severity of cognitive impairment at ‘baseline’ and to follow the course of cognitive changes over time. We defined ‘baseline’ as the first time a patient was diagnosed CHIR98014 mouse or assessed at our institution. 2.3 Statistical Methods Summary tables were used to describe the frequency and proportion of patients, as well as mean or median of sociodemographic and clinical characteristics and outcomes, by diagnostic groups (mixed AZD2281 AD and pure AD). Line plots were used to depict the evolution of outcomes over time, at the patient level and the diagnostic group level. The two-sample t-test and Kruskal–Wallis test were used to compare means and
medians, respectively, of continuous variables between diagnosis groups. Fisher’s exact test was used to test associations between categorical variables and diagnosis groups. Linear mixed models (LMM) with patient-specific random effects were used to evaluate the evolution of the outcomes over time while accommodating the dependence in the data, due to repeated assessments of each patient over time; identifying and adjusting for potential confounders;
and accounting for missingness in the data [25–27]. Results from LMM were valid under the missing at random missingness assumption, which implied that, conditional on the observed data, the missingness was independent of the unobserved Rucaparib assessments [28, 29]. Patient-specific random effects and an unstructured (general) variance-covariance matrix were used to account for the differences in number of assessments as well as duration between assessments, between patients. First, a ‘base-model’ was developed based on diagnosis group, follow-up time, and patient-specific random effects only. Second, each sociodemographic and clinical characteristic was added separately to the base model in order to identify potential confounders. We henceforth refer to such models as univariable models. Third, a final model was developed by adding all potential confounders simultaneously to the base model, henceforth referred to as multivariable models. Medication was considered as a time varying covariate in the univariable and multivariable models. Appropriate mixture of Chi-squared tests were used to test the variances of the patient-specific random effects [26, 27]. The significance level was set at 5 % and all tests were two-sided. SAS version 9.2 software (SAS Institute, Cary, NC, USA) was used for the analyses. 3 Results 3.1 Baseline Characteristics A total of 165 patients (137 [83 %] mixed AD patients and 28 [17 %] pure AD patients), met the study eligibility criteria, of whom 140 (84.