Effectiveness of the booster dose of COVID-19 vaccine in the Basque Country during the sixth wave: A nationwide cohort study

The aim of the study was to assess the effect of a booster dose of COVID-19 vaccine on the rates of hospital ward and intensive care unit (ICU) admissions around the time of emergence of the Omicron variant in the Basque Country. A retrospective cohort population-based study was conducted. The population with any records related to COVID-19 vaccination up to 28 February 2022 was classified into four cohorts by vaccination status. For every cohort, the hospital ward and ICU admission rates were calculated for each day between November 2021 and February 2022. Generalized linear models with a negative binomial distribution were used to estimate the age-adjusted hospitalization rate ratio of the cohort of individuals who had received a booster compared to the other cohorts. The age-adjusted rates of hospital ward and ICU admissions were 70.4 % and 72.0 % lower, respectively, in the fully vaccinated plus booster group compared to the fully vaccinated but no booster group. Analysing changes in the 14-day admission incidence rates showed that as the prevalence of the Omicron variant increased, the corresponding rate ratios decreased. The immunity acquired with the booster dose allowed the hospital network to meet all the demand for hospitalization during a period of high incidence of COVID-19, despite the fact that vaccine protection decreased as the prevalence of the Omicron variant increased.

[Factors associated with hypoalphalipoproteinemia]

BACKGROUND

Hypoalphalipoproteinemia (HALP) is the most frequent lipid alteration found in patients with myocardial infarction at an early age. It is defined by amounts of lipid cholesterol at high density lipoproteins (cHDL) lower than 10% according to age and sex. The aim of this study was to know the frequency of main factors which reduce the levels of cHDL in a group of subjects with and without HALP.

METHODS

Pathological antecedents, consumption of drugs, alcohol and cigarettes, the presence of obesity and levels of cholesterol, triglycerides, cHDL, glucose and urea were studied in a group of 1825 males. The study was performed in the course of medical examinations for workers.

RESULTS

The consumption of cigarettes, the index of body mass (IBM) and the prevalence of diabetes mellitus were higher in the group of subjects with HALP. Hypertriglyceridemia (triglycerides > or = 200 mg/dl) was found in 31% of the subjects with HALP vs 10% in the control group (p < 0.001); hypocholesterolemia (cholesterol < or = 150 mg/dl) was also significantly greater (9.8% vs 4.3%, p < 0.01). Altogether, in 64% of the subjects with HALP, factors which may decrease cHDL were associated. Of the factors studied, the number of triglycerides, IBM and the number of cigarettes consumed per day were the independent factors which most significantly contributed to the decrease of cHDL in the regression analysis.

CONCLUSIONS

Most of the subjects with hypoalphalipoproteinemia present other modifiable factors such as an elevated index of body mass, cigarette consumption and high amounts of triglicerydes, the correction of which constitutes the base for treatment of this disorder.