The effect of MDA regimens on mechanisms of action of azithromycin
malaria, inflammation, parasitemia, parasitaemia, intestinal inflammation
MALARIA, INFLAMMATION, PARASITEMIA, INTESTINAL INFLAMMATION, REGRESSION
Outcomes related to study questions on mechanisms of action of azithromycin are measured twice: at day 0, i.e., before the treatment on the day of fourth MDA visit (9 months after village enrolment), and 14 days after. The two intervention groups will be combined in the analysis. For each endpoint in the mechanistic study, mixed-effects regression model with random intercepts for clusters will be estimated, including intervention (versus control) and the day 0 measure as the independent variables and the day 14 measure as the dependent variables.To investigate the impact of AZI MDA on malaria parasitaemia prevalence, the prevalence of elevated CRP concentration (CRP > 5 µg/mL), prevalence of elevated AAT concentration (AAT > 270 µg/g), MPO concentration (MPO > 2000 ng/L), and NEO concentration (NEO > 70 nmol/L), we will use the binary variables as dependent outcome variables in mixed-effects logistic regression models with random intercepts for clusters and for children. The marginal risk ratios will be predicted from the obtained model coefficients. Risk ratios and their 95% CIs will be reported.We will model the impact of AZI MDA on the intensity of subclinical malaria by using the natural logarithm transformed values from the parasite density variable as the dependent outcome variable in a mixed-effects model with random intercepts for clustering and identity link function. We will use the same modeling approach on modeling the impact of AZI MDA on general inflammation and intestinal inflammation (that is, CRP concentration, AAT concentration, MPO concentration, and NEO concentration, respectively). We will report the exponentiated value of the regression coefficient (geometric mean) and their 95% CI. We will conduct the same analysis with the blood hemoglobin concentration as the dependent outcome variable but report regression coefficients and their 95% CIs without exponentiation.We will also produce tabulations on the descriptive summaries (means, medians, standard deviations, minimum, maximum) of the variables and report proportions and absolute numbers on positive and negative malaria parasitemia prevalences, as well as proportions and absolute numbers on elevated CRP/AAT/MPO/NEO concentration levels. The tabulations will be done respectively for day 0 and day 14.