Acquired QT Prolongation

Nocturia and electrocardiographic abnormalities among patients at an inner-city cardiology clinic

AIMS

Nocturia has been increasingly recognized as a potential manifestation of cardiovascular disease. However, the relationship between nocturia and electrocardiographic (ECG) abnormalities has not been studied. This study aims to characterize the diagnostic utility of nocturia in identifying left ventricular hypertrophy (LVH), left atrial enlargement (LAE), and prolonged QTc on ECG.

METHODS

Retrospective analysis of nocturnal voiding frequency and contemporaneous ECG data from consecutive patients evaluated at a university-based outpatient cardiology clinic. Three sets of three incremental binary multiple logistic regression models controlling for (1) age, (2) sex and race, and (3) body mass index, hypertension, diabetes mellitus, and diuretic utilization were performed to determine whether nocturia was predictive of LVH, LAE, and prolonged QTc.

RESULTS

Included patients (n = 143, 77.6% nocturia) were predominantly African-American (89.5%), female (74.1%), and obese (61.5%), of whom 44.1%, 41.3%, and 27.3% had LVH, LAE, and prolonged QTc, respectively. Older age, African-American race, obesity, hypertension, diuretic use, LVH, and LAE were significantly associated with nocturia on univariate analysis. No significant differences were observed in the strength of associations between nocturia and LVH, LAE, or QTc prolongation based on age. Nocturia independently predicted LVH in Models I-III (odds ratios [ORs], 2.99-3.20; relative risks [RRs], 1.18 for all, p ≤ .046) and LAE in Models I-III (ORs, 4.24-4.72; RRs, 1.21 for all, p ≤ .015). No significant associations were observed between nocturia and prolonged QTc.

CONCLUSIONS

Nocturia may be a risk marker for underlying structural cardiac abnormalities.

Sex differences in the pharmacology of itch therapies-a narrative review

BACKGROUND

Chronic itch is the most common skin-related condition, associated with a high psychosocial and economic burden. In recent years, increasing evidence of sex differences in the perception, clinical presentation and treatment requirements of itch points towards potential benefits when using sex-adapted therapies. It is well-known that body composition, absorption, metabolism, elimination and adverse drug reactions (ADRs) differ between sexes, but only little is known about the impact of sex in the pharmacology of itch treatments, which could help to rationalise sex-adapted treatment strategies.

AIM

To evaluate and review sex effects in the pharmacokinetics and /-dynamics of drugs used to treat itch.

METHODS

In this narrative review we performed a PubMed and MEDLINE (Ovid) search using the terms (itch OR pruritus) AND (gender OR sex) AND (drug OR medication OR pharmacokinetics OR pharmacodynamics). Additional searches were performed for the topical and systemic drugs recommended by the European Guideline on Chronic Pruritus.

RESULTS

We found numerous reports with variable levels of evidence of sex effects with respect to the pharmacokinetics and/or pharmacodynamics of 14 drug classes used for the treatment of itch, including a total of 19 systemic and 3 topical drugs. Women seem to present higher plasma levels of several drugs used in itch treatment, including tri- and tetracyclic antidepressants (e.g. doxepin, amitriptyline, mirtazapine), serotonin reuptake inhibitors (e.g. paroxetine, sertraline, fluoxetine), immunosuppressive drugs (e.g. cyclosporine, mycophenolate mofetil), serotonin receptor antagonists (e.g. ondansetron) and betablockers (e.g. propranolol). Adverse drug reactions (ADRs) were generally more common in women. Being female was reported to be an independent risk factor for QTc-prolongation associated with antihistamines and tetracyclic antidepressants. Additionally, women seem to be more prone to sedative effects of antihistamines, and to suffer from a higher frequency as well as severity of side effects with systemic calcineurin inhibitors, opioid agonists, and opioid antagonists. Women were also sensitised more often to topically applied drugs. Of note, apart from only one experimental study with capsaicin, none of these reports were designed specifically to assess the effect of sex (and gender) in the treatment of itch.

DISCUSSION/CONCLUSION

Our review supports previous reports that sex is of importance in the pharmacokinetics and /-dynamics of several drugs used to treat itch although those drugs were mostly evaluated for non-itch indications. However, the results are limited by methodological limitations evident in most studies such as underrepresentation of women in clinical trials. This emphasises the need to study the impact of sex (and gender) in future itch trials to yield better outcomes and prevent ADRs in both sexes.