Effect of plasma carboxyhemoglobin level on gonadal hormone levels

In emergency departments, carbon monoxide (CO) is a common cause of toxic poisoning. We aimed to determine the relationship between plasma carboxyhemoglobin (COHb) levels and late post-treatment gonadal hormone changes in CO poisoning.

The study included 237 patients older than 18 who presented to the Emergency Department due to CO intoxication between January 2008 and December 2016. Patients with a COHb level of less than 30% were classified as having mild-to-moderate disease, while those with a COHb level of more than 30% were classified as having severe disease.

Of 41 (17%) patients with gonadal hormone change (GHC), 19 (46.3%) were females. In cases with GHC, the exposure time was 5.76±1.64 hours (P=0.001). COHb level was 50.46±4.43% in the severe group (P=0.001), while hormone levels were normal in women and men before CO poisoning. GHC within one month and two years after poisoning was significantly higher (P=0.001). There were 138 (58.2%) patients in the mild-to-moderate group, and 99 (41.8%) patients in the severe group. Of the gonadal hormones, LH2 (luteinizing hormone) was 13.54±3.40 mIU/mL, FSH2 (follicle-stimulating hormone) 16.69±4.35 mIU/mL, PRL2 (prolactin) 16.23±4.73 ng/mL, and TTN2 (testosterone) 644.06±120.40 (P=0.001). In addition, COHb was found to be 42.68±8.42% (P=0.001). In univariate and multivariate Cox regression analysis, gender, LH1, LH2, PRL2, TTN2 and COHb values were found to be prognostic signs in terms of endocrine gonadal hormone change (P<0.05). In the correlation of COHb level with GHC, positive moderate-strong correlation was found between LH2, FSH2, PRL2, TTN2 (P=0.001).

In patients admitted to the emergency services due to CO poisoning, elevated COHb may help predict the risk for late gonadal hormone levels.