Background This study investigated the correlation between a history of human papillomavirus (HPV) infection and skin cancer risk. Materials and Methods The study cohort comprised 26,919 patients with newly diagnosed HPV infection between 2000 and 2012; and with use of computer‐generated randomly numbers, patients not had HPV infection were randomly selected as the comparison cohort. HPV infection cohort were matched to comparison individuals at a 1:4 ratio by demographic characteristics and comorbidities. All study individuals were followed up until they developed skin cancer, withdraw from the National Health Insurance program, were lost to follow‐up, or until the end of 2013. The primary outcome was subsequent skin Cancer development. Cox proportional hazards regression analysis was used to analyze the risk of skin Cancer with hazard ratios (HRs) and 95% confidence intervals (CIs) between the HPV and control cohort. Results The adjusted HR of skin cancers for patients with HPV relative to controls was 2.45 after adjusting sex, age and comorbidities. (95% CI, 1.44–4.18, p < .01). The subgroup analysis indicated that a patient with HPV infections had a significantly greater risk of skin cancer if they were aged >40. Notably, the risk of skin cancers was found in group diagnosed with HPV within the first 5 years after index date (adjusted HR, 3.12; with 95% CI, 1.58–5.54). Sensitivity analysis by propensity score, matching with balanced sex, age, and comorbidities showed consistent results. Conclusions A history of HPV infection is associated with the development of subsequent skin cancer in Taiwanese subjects, and the risk wane 5 years later. Implications for Practice In this Taiwan nationwide cohort study, there was a 2.45‐fold increase risk of developing new‐onset skin cancers for patients with incident human papillomavirus (HPV) infection, compared with the matched controls. Furthermore, the risk was noticeably significant among aged more than 40 years. A prominent risk of skin cancers was found in group diagnosed with HPV within the first 5 years after index date in this study. The results of our analysis may raise consensus on the effect of HPV infection and skin cancers. Clinicians are suggested to implement prudently on the differential diagnosis of skin cancers and HPV prevention and treatment, especially in older patients.

OBJECTIVE: Previous studies have indicated a bidirectional correlation between diabetes and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, no investigation has comprehensively explored the potential of coronavirus disease 2019 (COVID-19) vaccination to reduce the risk of new-onset diabetes in infected individuals. RESEARCH DESIGN AND METHODS: In the first of 2 cohorts, we compared the risk of new-onset diabetes between individuals infected with SARS-CoV-2 and noninfected individuals (N = 1,562,606) using the TriNetX database to validate findings in prior literature. For the second cohort, we identified 83,829 vaccinated and 83,829 unvaccinated COVID-19 survivors from the same period. Diabetes, antihyperglycemic drug use, and a composite of both were defined as outcomes. We conducted Cox proportional hazard regression analysis for the estimation of hazard ratios (HRs) and 95% CIs. Kaplan-Meier analysis was conducted to calculate the incidence of new-onset diabetes. Subgroup analyses based on age (18–44, 45–64, ≥65 years), sex (female, male), race (White, Black or African American, Asian), and BMI categories (<19.9, 20–29, 30–39, ≥40), sensitivities analyses, and a dose-response analysis were conducted to validate the findings. RESULTS: The initial cohort of patients infected with SARS-CoV-2 had a 65% increased risk (HR 1.65; 95% CI 1.62–1.68) of developing new-onset diabetes relative to noninfected individuals. In the second cohort, we observed that vaccinated patients had a 21% lower risk of developing new-onset diabetes in comparison with unvaccinated COVID-19 survivors (HR 0.79; 95% CI 0.73–0.86). Subgroup analyses by sex, age, race, and BMI yielded similar results. These findings were consistent in sensitivity analyses and cross-validation with an independent data set from TriNetX. CONCLUSIONS: In conclusion, this study validates a 65% higher risk of new-onset diabetes in SARS-CoV-2–infected individuals compared to noninfected counterparts. Furthermore, COVID-19 survivors who received COVID-19 vaccinations experienced a reduced risk of new-onset diabetes, with a dose-dependent effect. Notably, the protective impact of COVID-19 vaccination is more pronounced among the Black/African American population than other ethnic groups. These findings emphasize the imperative of widespread vaccination to mitigate diabetes risk and the need for tailored strategies for diverse demographic groups to ensure equitable protection.

Background/Purpose: Flat foot can alter the lower limb alignment and cause knee and back pain. To explore the association between flat foot and spinal degeneration. Methods: By using a claims dataset containing 1 million random samples, individuals with flat foot were identified between January 1, 2000, and December 31, 2013. The study assembled a flat foot group and a matched non-flat foot group. Definition of flat foot was according to International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes. The diagnosis date was defined as the index date for follow-up initiation. The follow-up period was defined as the duration from the index date (or nested index date for controls) to the occurrence of spinal degenerative joint disease (DJD), or December 31, 2013. The primary outcome was record of spinal DJD retrieved from the same database. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs), with the control group as a reference. Results: We identified 13,965 patients (most aged 45 years with history of flat foot, the adjusted hazard ratios were 1.434, 3.065, 3.110, and 2.061 in association with spondylosis, intervertebral disc disorder, cervical stenosis, thoracic-lumbar-sacral stenosis, respectively. Conclusion: Flat foot was found to be an independent risk factor for subsequent spinal DJD. Copyright 2020, Formosan Medical Association. Published by Elsevier Taiwan LLC. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/bync-nd/4.0/).

Objective: To explore whether newly diagnosed iron deficiency anemia (IDA) is associated with subsequent systemic autoimmune disease onset. Methods: The study identified 22,440 patients who received a diagnosis of IDA between 2000 and 2012 from a random sample of 1 million people from Taiwan’s National Health Insurance Research Database. The patients with IDA were randomly matched with 89,528 patients with no IDA by age, gender, and index year. We followed the 2 groups until systemic autoimmune disease onset. Cox proportional hazards analysis was used to determine autoimmune disease risk by age, gender, and comorbidities, in terms of hazard ratios (HRs) and 95% confidence intervals (CIs). Results: Adjusted HR (95% CI) of autoimmune disease in the IDA group was 2.37 (1.92–2.92) compared with the non-IDA group. The subgroup analysis indicated that a patient with IDA had a significantly greater risk of an autoimmune disease if they were female or had the comorbidities of hypertension, hyperlipidemia, cancer, allergic rhinitis, urticaria, chronic obstructive pulmonary disease, or chronic liver disease. An autoimmune disease was significantly more likely to occur within 2 years after a new diagnosis of IDA. Conclusions: IDA significantly increases autoimmune disease risk, particularly in female patients and patients with certain comorbidities. Clinicians should conduct further clinical evaluations and laboratory tests of autoimmune disease in patients with IDA. Plain Language Summary: Little is known about the relationship between iron deficiency and autoimmune disease. By using a national-level database in Taiwan, we noted a meaningful association between iron deficiency anemia (IDA) and later autoimmune disease development. Our study extends the known disease range and recommends that physicians be alert for the occurrence of autoimmune disease after an IDA diagnosis. The subgroup analysis indicated that, among patients with IDA, female patients and patients with the simultaneous chronic diseases of allergic rhinitis, urticaria, cancer, chronic obstructive pulmonary disease (COPD), hyperlipidemia, or hypertension had a significantly higher risk of autoimmune disease. The risk of autoimmune disease was considerably higher within the 2 years after an IDA diagnosis.

Endometriosis (EM) with chronic inflammation may accelerate the progression of atherosclerosis. Currently, no large or randomized clinical studies have assessed the incidence of cardiovascular events in patients with endometriosis in Asia to investigate whether incident EM is associated with a higher risk of new-onset coronary artery disease (CAD). In this study of a nationwide cohort in Taiwan, we identified 13,988 patients with newly diagnosed EM from 1 January, 2000, through 31 December, 2012. EM and non-EM groups were matched by propensity score at a ratio of 1:1. Of a total 27,976 participants, 358 developed CAD. The incidence rate in the EM group was higher than that in the non-EM group (1.8 per 1,000 person-years vs. 1.3 per 1,000 person-years) during the follow-up period. The adjusted hazard ratio (aHR) of CAD for the EM group was 1.52 with a 95% confidence interval (1.23–1.87, p < 0.001) after adjusting for demographic characteristics, comorbidities, surgical procedures, frequency of outpatient visits, and medications. Stratified analysis revealed that, among four age groups (20–39, 40–49, 50–54, and above 55 years), the 20–39 years sub-group was associated with a higher risk of CAD (aHR, 1.73; 95% CI, 1.16–2.59, p = 0.008). Several sensitivity analyses were conducted for cross-validation, and it showed consistent positive findings. In conclusion, this cohort study revealed that patients with symptomatic EM in Taiwan were associated with increased risk of subsequent CAD than patients without medical records of EM. Further prospective studies are needed to confirm this causal relationship.