Effect of meteorological variables on the incidence of lower urinary tract infections

Effect of meteorological variables on the incidence

Matthew E. Falagas,1,2,3 MD, MSc, DSc, George Peppas,1,4 MD, PhD, Dimitrios K. Matthaiou,1 MD, Drosos E. Karageorgopoulos,1 MD, Nikolas Karalis,5 George Theocharis,4 MD

1. Alfa Institute of Biomedical Sciences (AIBS), Athens, Greece
2. Department of Medicine, Henry Dunant Hospital, Athens, Greece
3. Department of Medicine, Tufts University School of Medicine, Boston, Massachusetts, USA
4. SOS Doctors, Athens, Greece
5. National Technical University of Athens, Athens, Greece

Background

Several respiratory tract infectious diseases have a seasonal variation. We examined whether lower urinary tract infections (LUTIs) are associated with meteorological parameters.

Methods

We retrospectively examined the correlation of the weekly percentage of house call visits for LUTIs (relatively to all house call visits excluding those for respiratory tract infections), performed by “SOS Doctors” specialized physicians in Attica, Greece (1/11/2000-18/1/2005), with the average weekly temperature and

Results

Table 1. Correlation between weekly percentage of house call visits for urinary tract infections and average weekly meteorological variables.

Correlation examined Spearman’s rho p-value
Main analysis
% of house calls for urinary tract infections excluding visits for
respiratory tract infections vs. temperature 3 days earlier
0.468 <0.001
% of house calls for urinary tract infections excluding visits for
respiratory tract infections vs. average relative humidity 3 days earlier
-0.394 <0.001
Secondary analysis
% of house calls for urinary tract infections including visits for
respiratory tract infections vs. average temperature 3 days earlier
0.491 <0.001
% of house calls for urinary tract infections including visits for
respiratory tract infections vs. average relative humidity 3 days earlier
-0.406 <0.001
% of house calls for urinary tract infections excluding visits for
respiratory tract infections vs. temperature 2 days earlier
0.468 <0.001
% of house calls for urinary tract infections excluding visits for
respiratory tract infections vs. average relative humidity 2 days earlier
-0.386 <0.001

Three thousand two hundred and twenty-one visits for LUTIs were recorded in patients of 62.9±21.0 years of age. House call visits for LUTIs, as defined above, correlated with average weekly temperature (Spearman’s rho +0.468) and humidity (Spearman’s rho -0.394); also if respiratory tract infections were not excluded from the calculations (Spearman’s rho +0.491 and -0.406, respectively); or if a 2-day lag between measurements was used (Spearman’s rho +0.468 and -0.386, respectively). All findings were significant (p<0.001).
Conclusions In a population that consisted mainly of patients of advanced age, higher temperature and decreased humidity are associated with an increase in house call visits for LUTIs. The awareness of this association may facilitate preventive public health strategies.

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