Sociodemographic factors and uncomplicated pyelonephritis in women aged 15-50 years: a nationwide Swedish cohort register study (1997-2018)

The Risk of Pyelonephritis Following Uncomplicated Cystitis: A Nationwide Primary Healthcare Study

BACKGROUND

The risk of pyelonephritis following uncomplicated lower urinary tract infection (cystitis) in women has not been studied in well-powered samples. This is likely due to the previous lack of nationwide primary healthcare data. We aimed to examine the risks of pyelonephritis following cystitis in women and explore if antibiotic treatment, cervical cancer, parity, and sociodemographic factors are related to these risks.

METHODS

This was a nationwide cohort study (2006-2018) of 752,289 women diagnosed with uncomplicated cystitis in primary healthcare settings. Of these, 404 696 did not redeem an antibiotic prescription within five days from cystitis. Logistic regression models were used to calculate odds ratios for pyelonephritis within 30 days and 90 days following the cystitis event.

RESULTS

Around one percent (7454) of all women with cystitis were diagnosed with pyelonephritis within 30 days, of which 78.2% had not redeemed an antibiotic for their cystitis. Antibiotic treatment was inversely associated with both outpatient registration and hospitalization due to pyelonephritis, with odds ratios of 0.85 (95% CI 0.80 to 0.91) and 0.65 (95% CI 0.55 to 0.77), respectively. Sociodemographic factors, parity, and cervical cancer were, with few exceptions (e.g., age and region of residency), not associated with pyelonephritis.

CONCLUSIONS

Antibiotic treatment was inversely associated with pyelonephritis, but the absolute risk reduction was low. Non-antibiotic treatment for cystitis might be a safe option for most women. Future studies identifying the women at the highest risks will help clinicians in their decision making when treating cystitis, while keeping the ecological costs of antibiotics in mind.

The relation of body mass index, body height, and parity to pyelonephritis: A nationwide population-based cohort study of over one million parous women (1997-2018)

OBJECTIVES

We aimed to explore the association between various physiological factors and pyelonephritis in parous women.

METHODS

Swedish nationwide registers were used to identify 1,073,467 parous women aged 15-50 years. The study period began in 1997 and ended in 2018, or at the first incidence of pyelonephritis, death, or emigration. Cox proportional hazards methods were used to determine hazard ratios (HRs) and 95% confidence intervals (CIs) of pyelonephritis in relation to body mass index (BMI) and body height adjusted for age, parity, and individual-level sociodemographic variables.

RESULTS

A total of 21,625 women (2.0%) were diagnosed with pyelonephritis during follow-up. In the fully adjusted model, low BMI (<18.5) was associated with pyelonephritis (HR 1.13, 95% CI 1.06-1.21). Parity and certain sociodemographic characteristics were also independently associated with pyelonephritis. Body height <161 cm was associated with pyelonephritis (HR 1.12, 95% CI 1.09-1.16) in all but the fully adjusted model.

CONCLUSION

Low BMI and body height seem to be associated with uncomplicated pyelonephritis. More research is needed to verify these findings and identify possible mechanisms.

Elucidating the effect of body mass index, height, and parity on uncomplicated cystitis: a nationwide population-based cohort study

In this nationwide cohort of one million fertile women, BMI, height, and parity only had minor but statistically significant effects on the risk of uncomplicated cystitis. The results indicate that underweight women and certain sociodemographic groups might have higher risks, which could have underlying explanations that need further studying.

Sociodemographic Disparities and Parity in Relation to Urinary Incontinence: A Nationwide Primary Healthcare Cohort Study (1997–2018)

Objectives: Urinary incontinence (UI) is a very common condition in the primary healthcare settings. Few studies have investigated whether sociodemographic factors are related to UI. This nationwide study aimed to investigate whether there is a relationship between sociodemographic factors and UI in women. Methods: A nationwide open cohort study included 2,044,065 women aged 15–50 years. Several national population-based (Sweden) databases including nationwide primary healthcare data were used. The outcome was the time to the first event of any UI diagnosis during the study period (1997–2018). Cox regression models were used to test for associations between individual sociodemographic factors and UI. Results: The study identified 44,250 UI events. These corresponded to 2.16% of the study population and an incidence rate (IR) per 1000 person-years of 1.85 (95% CI 1.84–1.87). In the fully adjusted model, a high age, low education level, and being born outside of Sweden were independently associated with a higher UI risk, while rural living was associated with a lower risk. The income level did not seem to have a large impact. Most notably, women born in the Middle East/North Africa and Latin America/Caribbean had a substantially higher risk of UI with HRs of 2.41 (95% CI 2.33–2.49) and 2.30 (95% CI 2.17–2.43), respectively. Parity was strongly and independently associated with UI. Conclusion: This study presents novel risk factors associated with UI. The findings provide new knowledge concerning the burden of this disease among women, which could be used to provide more equal healthcare for these patients in the future. Previous research allied with these findings suggests using a comprehensive approach targeting health disparities.

Novel risk factors associated with common vaginal infections: a nationwide primary healthcare cohort study

OBJECTIVE

To estimate the association between potential risk factors and common vaginal infections, using nationwide primary healthcare and other national register.

METHODS

An open cohort study consisting of 2 357 711 women aged 15-50 years (2001-2018) was conducted in Sweden. The outcomes were first event of vulvovaginal candidiasis (VVC) and bacterial vaginosis (BV) in relation to sociodemographic factors. Cox regression models were used. Sensitivity analyses including diabetes mellitus, contraceptive use, and cervical cancer were conducted.

RESULTS

The incidence rates per 1000 person-years for VVC and BV were 3.3 (95% CI 3.2-3.3) and 3.4 (95% CI 3.4-3.4), respectively. In the fully adjusted model, sociodemographic factors were significantly associated with both outcomes. Compared to Swedish-born women, women from Middle East/North Africa had the highest risk of VVC (HR 2.77, 95% CI, 2.72-2.83), followed by Africa (excluding North Africa) (HR 2.53, 95% CI, 2.45-2.61), and Latin America and the Caribbean (HR 2.18, 95% CI, 2.09-2.27). For BV, women from Latin America and the Caribbean had the highest risk (HR 1.83, 95% CI, 1.75-1.92).

CONCLUSION

This study presents novel risk factors associated with medically attended vaginal infections. Women from non-western countries seem to suffer disproportionately from these conditions.

The Effect of Sociodemographic Factors, Parity and Cervical Cancer on Antibiotic Treatment for Uncomplicated Cystitis in Women: A Nationwide Cohort Study

BACKGROUND

Uncomplicated cystitis is one of the most common reasons for antibiotic treatment in otherwise healthy women. Nationwide studies on antibiotic treatment for this infection and in relation to factors beyond the infection itself have hitherto not been available.

METHODS

This was a nationwide open cohort study consisting of 352,507 women aged 15-50 years with uncomplicated cystitis (2006-2018). The outcome was a redeemed antibiotic prescription within five days from the cystitis diagnosis. Logistic regression models were used to examine the relationship between the outcome and the predictor variables.

RESULTS

This study identified 192,065 redeemed treatments (54.5%). Several sociodemographic variables were associated with antibiotic treatment. For example, women with the lowest income had an odds ratio (OR) of 1.26 (95% CI 1.23-1.28) compared to those with the highest income. History of cervical cancer and high parity were also associated with lower treatment rates.

CONCLUSION

This study presents novel factors beyond the infection which seem to affect the antibiotic treatment for uncomplicated cystitis in women. Future studies to investigate possible mechanisms are warranted in order to properly use our findings. This may help healthcare workers and planners to provide a more equal treatment plan for this common infection, which may reduce misuse of antibiotics, decrease costs and improve efforts against antibiotic resistance.