Adverse dermatologic effects of cardiovascular drug therapy: part II

Hydrochlorothiazide use, sun exposure, and risk of keratinocyte cancer

Background

Keratinocyte cancer (KC) rates are increasing in the U.S., particularly in older age groups. Use of hydrochlorothiazide (HCTZ), due to its photosensitizing properties, and high sun exposure are two known NMSC risk factors, but their synergistic effects are undetermined. The purpose of this study was to examine the development of NMSC between adults who did and did not use HCTZ, as well as those with high and low sun exposure.

Methods

A retrospective case–control sample was assembled from adult patients in north-central Wisconsin (USA). Duration of HCTZ use and occupational sun exposure were extracted from electronic health records, along with a linked survey of lifetime sun exposure.

Results

There were 333 cases and 666 controls in the analytical sample. A significant main effect was observed for HCTZ duration in the full sample. Under low sun exposure, the odds of NMSC was 14% greater for each additional year of HCTZ use (aOR = 1.14 [1.11, 1.18], p < 0.001). In a sensitivity analysis of participants age 70 years and over, there was a borderline significant (p = 0.086) HCTZ use by high sun exposure interaction, suggesting modestly increased HCTZ risk in older, high sun exposure adults.

Conclusions

Consistent with prior studies, longer duration of HCTZ use was a predictor of NMSC in north-central Wisconsin adults. NMSC may be accelerated in HCTZ users with outdoor lifestyles, but future studies should attempt to further disaggregate specific effects of sun exposure time, HCTZ duration, and age on NMSC development.

Antihypertensive drugs and lip cancer in non-Hispanic whites

BACKGROUND

In screening pharmaceuticals for possible carcinogenic effects we noted an association between lip cancer risk and the photosensitizing antihypertensive drugs hydrochlorothiazide and nifedipine. In this study, we further characterized the risk of lip cancer associated with these and other commonly used antihypertensive drugs.

METHODS

In a comprehensive medical care program, we evaluated prescriptions dispensed and cancer occurrence from August 1, 1994, to February 29, 2008. We identified 712 patients with lip cancer (cases) and 22,904 comparison individuals (controls) matched for age, sex, and cohort year of entry in the susceptible group, non-Hispanic whites. We determined use, at least 2 years before diagnosis or control index date, of the commonly prescribed diuretics hydrochlorothiazide and hydrochlorothiazide combined with triamterene, the angiotensin-converting enzyme inhibitor lisinopril, the calcium channel blocker nifedipine, and the β-adrenergic blocker atenolol, the only nonphotosensitizer agent studied. We analyzed the use of each drug exclusively and regardless of use of the others, and focused on duration of use. Conditional logistic regression was used for analysis of matched case-control sets, with control for cigarette smoking.

RESULTS

At least a 5-year supply of a drug yielded the following odds ratios (95% CIs), respectively, compared with no use: hydrochlorothiazide, 4.22 (2.82-6.31); hydrochlorothiazide-triamterene, 2.82 (1.74-4.55); lisinopril, 1.42 (0.95-2.13); nifedipine, 2.50 (1.29-4.84); and atenolol, 1.93 (1.29-2.91). When the other drugs were excluded, the odds ratio for atenolol was reduced to 0.54 (0.07-4.08).

CONCLUSION

These data support an increased risk of lip cancer in non-Hispanic whites receiving treatment for hypertension with long-term use of photosensitizing drugs.

Non-melanoma skin cancers in elderly patients

Non-melanoma skin cancers are a common reality worldwide. The principal cause that determines the occurrence of these diseases is the exposition of the sun, which principally causes an alteration in the immune system. Therefore, it is possible that other forms of innate or acquired alterations of the immune system could favor the occurrence of non-melanoma skin cancers. For example, several studies have demonstrated that immunosenescence creates an immunosuppressive state that encourages the development of malignances, and new discoveries have noted the importance of T cells and in particular of T regulatory cells (Treg) and T receptor CD28 in this mechanism. Similar results are obtained analyzing the effect of immunosuppressive drugs. The importance of the immune system and its alteration in the genesis of non-melanoma skin cancers is fundamental for the creation of a new therapeutic and less invasive approach.

Calcium channel blocker-associated small bowel angioedema

INTRODUCTION

Isolated angioedema of the small intestine is a rare entity. The cases described have been related with angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, or C1 esterase inhibitor deficiency. We present a case of small intestine angioedema caused by calcium channel blockers (CCBs) and a review of the literature.

CASE REPORT

Over the course of approximately 2 years, a 56-year-old African American woman presented to our hospital with 8 similar episodes of diffuse, intermittent abdominal pain, nausea, vomiting, and diarrhea. The diagnostic workup was extensive and included normal stool studies, anticardiolipin antibodies, antinuclear antibodies, antineutrophil cytoplasmic antibodies, cryoglobulin studies, complement levels, urinary 5-hydroxyindoleacetic acid, and serum markers for inflammatory bowel diseases. A computed tomographic angiogram was normal. Abdominal computed tomographic scans showed prominent mural thickening of different intestinal segments, always involving the ileum. An esophagogastroduodenoscopy showed patchy edematous, violaceous folds in the second portion of the duodenum. Colonoscopy revealed a markedly edematous and erythematous distal ileum. The recurrences subsided after CCBs were discontinued in this patient and reoccurred when they were incidentally restarted.

CONCLUSIONS

Our case demonstrates that CCBs can cause isolated intestinal angioedema with distinctive endoscopic findings. The discontinuation of the involved medication is the key for both diagnosis and treatment.

Use of photosensitising diuretics and risk of skin cancer: a population-based case-control study

Diuretics have photosensitising properties. However, little is known about how these diuretics affect the risk of skin cancers. In North Jutland County, Denmark, we investigated whether the use of photosensitising diuretics was associated with an increased risk for developing basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and malignant melanoma (MM). From the cancer registry, we identified primary cases of BCC, SCC and MM during the period of 1989-2003. We selected four population controls for each case from the Danish Civil Registration System, matched on age and gender. Prescriptions for photosensitising diuretics before cancer diagnosis were ascertained in the county's Prescription Database. We used conditional logistic regression to compute incidence rate ratio (IRR), controlling for the chronic medical conditions and for the previous use of oral glucocorticoids. We found an increased risk of SCC (IRR of 1.79 (95% confidence interval (CI): 1.45-2.21)) and MM (IRR of 1.43 (95% CI: 1.09-1.88)) among users of combined amiloride and hydrochlorothiazide therapy. An increased risk of MM (IRR of 3.30 (95% CI: 1.34-8.10)) was found among users of indapamide. We found little associations with risk of BCC. Our findings provide evidence that the use of some photosensitising diuretics is associated with an increased risk for SCC and MM.