Men's health, low testosterone, and diabetes: individualized treatment and a multidisciplinary approach

Anthropometric and hormonal risk factors for male breast cancer: male breast cancer pooling project results

BACKGROUND

The etiology of male breast cancer is poorly understood, partly because of its relative rarity. Although genetic factors are involved, less is known regarding the role of anthropometric and hormonally related risk factors.

METHODS

In the Male Breast Cancer Pooling Project, a consortium of 11 case-control and 10 cohort investigations involving 2405 case patients (n = 1190 from case-control and n = 1215 from cohort studies) and 52013 control subjects, individual participant data were harmonized and pooled. Unconditional logistic regression generated study design-specific (case-control/cohort) odds ratios (ORs) and 95% confidence intervals (CIs), with exposure estimates combined using fixed effects meta-analysis. All statistical tests were two-sided.

RESULTS

Risk was statistically significantly associated with weight (highest/lowest tertile: OR = 1.36; 95% CI = 1.18 to 1.57), height (OR = 1.18; 95% CI = 1.01 to 1.38), and body mass index (BMI; OR = 1.30; 95% CI = 1.12 to 1.51), with evidence that recent rather than distant BMI was the strongest predictor. Klinefelter syndrome (OR = 24.7; 95% CI = 8.94 to 68.4) and gynecomastia (OR = 9.78; 95% CI = 7.52 to 12.7) were also statistically significantly associated with risk, relations that were independent of BMI. Diabetes also emerged as an independent risk factor (OR = 1.19; 95% CI = 1.04 to 1.37). There were also suggestive relations with cryptorchidism (OR = 2.18; 95% CI = 0.96 to 4.94) and orchitis (OR = 1.43; 95% CI = 1.02 to 1.99). Although age at onset of puberty and histories of infertility were unrelated to risk, never having had children was statistically significantly related (OR = 1.29; 95% CI = 1.01 to 1.66). Among individuals diagnosed at older ages, a history of fractures was statistically significantly related (OR = 1.41; 95% CI = 1.07 to 1.86).

CONCLUSIONS

Consistent findings across case-control and cohort investigations, complemented by pooled analyses, indicated important roles for anthropometric and hormonal risk factors in the etiology of male breast cancer. Further investigation should focus on potential roles of endogenous hormones.

Validity and reliability of male andropause symptoms self-assessment questionnaire among elderly males in Khuzestan province of Iran

Background:

Andropause is a condition of decreasing testosterone in men that usually begins to occur at about 40 years of age. Many men find it difficult to acknowledge there may be a problem by refusing to even talk about the symptoms.

Aims:

The study was conducted to the standards of MASSQ (2012) within male older adults to introduce a relevant criterion.

Materials and Methods:

About 382 men with age range of 50-80 and with the mean age of 65.3 ± 2.32 were sampled with the cluster-ratio sampling method from the eight cities of Khuzestan province in southwestern Iran. The aged samples replied to the 25 items of MASSQ.

Results:

Coefficients of Cronbach's alpha (α = 0.89), split-half (0.91), convergent validity (0.72), divergent validity (−0.32), and criterion validity (0.67) were estimated, which were significant at P < 0.01. The exploratory factor analysis demonstrated that the 25-items of MASSQ for aged samples are organized into four factors (sexual, somatic, psychic, and behavioral) which clarify 79% of the scale's variance. Second-order confirmatory factor analysis pointed out that the factors are well-matched up onto a principal factor. Consequently, the four-factor model was well appropriate for the data by the fit index techniques for adjusting the scale [adjusted goodness of fit index = 0.92, goodness-of-fit statistic = 0.91, root mean square error of approximation = 0.006, incremental fit index = 0.94, normed fit index = 0.91, comparative fit index = 0.97].

Conclusions:

The results pointed to the well-adjusted reliability and validity of MASSQ and its usefulness for the relevant studies as well.

Diabetes and cause-specific mortality in a prospective cohort of one million U.S. adults

OBJECTIVE

Diabetes is a major predictor of death from heart disease and stroke; its impact on nonvascular mortality, including specific cancers, is less understood. We examined the association of diabetes with cause-specific mortality, including deaths from specific cancers.

RESEARCH DESIGN AND METHODS

A prospective cohort of 1,053,831 U.S. adults, without cancer at baseline, enrolled in the Cancer Prevention Study-II in 1982 and was followed for mortality until December 2008. At baseline, participants completed a self-administered questionnaire that included information on diabetes, smoking, physical activity, height, and weight. Multivariable-adjusted relative risks (RRs) (95% CI) were estimated using Cox proportional hazards regression.

RESULTS

During 26 years of follow-up, 243,051 men and 222,109 women died. In multivariable models that controlled for age, BMI, and other variables, diabetes was associated with higher risk of all-cause mortality (women RR 1.90 [95% CI 1.87-1.93]; men 1.73 [1.70-1.75]). Among women, diabetes was associated with higher risk of death from cancers of the liver (1.40 [1.05-1.86]), pancreas (1.31 [1.14-1.51]), endometrium (1.33 [1.08-1.65]), colon (1.18 [1.04-1.33]), and breast (1.16 [1.03-1.29]). Among men, diabetes was associated with risk of death from cancers of the breast (4.20 [2.20-8.04]), liver (2.26 [1.89-2.70]), oral cavity and pharynx (1.44 [1.07-1.94]), pancreas (1.40 [1.23-1.59]), bladder (1.22 [1.01-1.47]), colon (1.15 [1.03-1.29]), and (inversely) prostate (0.88 [0.79-0.97]). Diabetes was also associated with higher risks of death involving the circulatory system, respiratory system, digestive system, genitourinary system, and external causes/accidental deaths.

CONCLUSIONS

Diabetes is associated with higher risk of death for many diseases, including several specific forms of cancer.

Testosterone replacement therapy among elderly males: the Testim Registry in the US (TRiUS)

Background:

Testosterone levels naturally decline with age in men, often resulting in testosterone deficiency (hypogonadism). However, few studies have examined hypogonadal characteristics and treatment in older (≥65 years) men.

Objective:

To compare data at baseline and after 12 months of testosterone replacement therapy (TRT) in hypogonadal men ≥65 vs <65 years old. Data for participants 65–74 vs ≥75 years old were also compared.

Methods:

Data were from TRiUS (Testim Registry in the United States), which enrolled 849 hypogonadal men treated with Testim^® 1% (50–100 mg testosterone gel/day) for the first time. Anthropometric, laboratory, and clinical measures were taken at baseline and 12 months, including primary outcomes of total testosterone (TT), free testosterone (FT), and prostate-specific antigen (PSA) levels. Comparisons of parameters were made using Fisher’s exact test or analysis of variance. Nonparametric Spearman’s ρ and first-order partial correlation coefficients adjusted for the effect of age were used to examine bivariate correlations among parameters.

Results:

Of the registry participants at baseline with available age information, 16% (133/845) were ≥65 years old. They were similar to men <65 years old in the duration of hypogonad-ism prior to enrollment (∼1 year), TT and FT levels at baseline, TT and FT levels at 12-month follow-up, and in reported compliance with treatment. Older patients were more likely to receive lower doses of TRT. PSA levels did not statistically differ between groups after 12 months of TRT (2.18 ± 2.18 ng/mL for ≥65 vs 1.14 ± 0.84 ng/mL for <65 years old, P = 0.1). Baseline values for the >75-year-old subcohort were not significantly different from subcohorts aged 65–74 years and <65 years.

Conclusion:

Hypogonadal men ≥65 years old showed significant benefit from TRT over 12 months, similar to that found for hypogonadal men <65 years old. TRT was well tolerated in older patients, successfully increased testosterone level regardless of age, and did not significantly increase PSA levels in older men.

High-normal Glucose Levels in Non-diabetic and Pre-diabetic Men Are Associated with Decreased Testosterone Levels

Background

Testosterone levels are decreased in diabetic patients and recent studies have suggested that high-normal fasting glucose is a risk factor for cardiovascular disease. To further elucidate the relationship between plasma glucose and testosterone, we investigated the association between fasting plasma glucose (FPG) and endogenous sex hormones (serum total testosterone, sex hormone binding globulin, estradiol, and the ratio of testosterone to estradiol) in non-diabetic and pre-diabetic men.

Methods

This study included 388 men (age ≥ 40 years) who visited the health promotion center of a university hospital from May 2007 to August 2008. The subjects were divided into quartiles based on their FPG levels and correlation and multiple linear regression analyses were performed. Q1 (65 mg/dL ≤ FPG < 88 mg/dL), Q2 (88 mg/dL ≤ FPG < 94 mg/dL), Q3 (94 mg/dL ≤ FPG < 100 mg/dL) and Q4 (100 mg/dL ≤ FPG < 126 mg/dL).

Results

FPG was independently, inversely associated with total testosterone in the non-diabetic population after adjusting for age, body mass index, smoking, and alcohol consumption (β = -0.082, P < 0.01). Among the quartiles, subjects in the high-normal FPG groups (Q2, Q3, and Q4 with FPG ≥ 88 mg/dL) had significantly decreased testosterone levels when compared with subjects in the normal FPG group (Q1 with FPG < 88 mg/dL, P < 0.005). Sex hormone binding globulin, estradiol and the ratio of testosterone to estradiol were not correlated with FPG.

Conclusion

Our study indicates that high-normal fasting glucose levels are associated with decreased testosterone levels in non-diabetic and pre-diabetic men.

Etiologic factors for male breast cancer in the U.S. Veterans Affairs medical care system database

The etiology of male breast cancer is largely unknown, reflecting its relative rarity. Although a number of previous studies have suggested relationships with a variety of medical conditions, the results have largely derived from case-control studies and may reflect recall biases. Within the large U.S. Veterans Affairs computerized medical care system database, we had the opportunity to access 26 million hospital discharge records over the period 1969-1996 and to relate various documented medical conditions to the risk of subsequent male breast cancer. This allowed us to calculate relative risks (RR) and 95% confidence intervals (CI) for male breast cancer associated with conditions occurring one or more years after initial hospitalization, adjusted for age, race, calendar year, duration of follow-up, and number of hospital visits. Among 4,501,578 men aged 18-100 years, a total of 642 cases of primary male breast cancer were identified (523 among whites, 119 among blacks). Medical conditions that were significantly related to risk were diabetes (RR 1.30, 95% CI 1.05-1.60), obesity (1.98, 1.55-2.54), orchitis/epididymitis (1.84, 1.10-3.08), Klinefelter syndrome (29.64, 12.26-71.68), and gynecomastia (5.86, 3.74-9.17). Additionally, among black patients, cholelithiasis emerged as a significant risk predictor (3.45, 1.59-7.47). Diseases that have previously been related to male breast cancer risk that were not supported by our study results included thyroid diseases, smoking-related conditions, liver cirrhosis, prostatic hyperplasia, and fractures. After adjustment for obesity, the association with diabetes disappeared, but that with gynecomastia persisted. In multivariate models that simultaneously considered all important medical predictors of risk, significant risks were seen for Klinefelter syndrome (16.83, 6.81-41.62), gynecomastia (5.08, 3.21-8.03), obesity (1.91, 1.50-2.44), and orchitis/epididymitis (1.80, 1.08-3.01). These results support previous speculations that male breast cancer is influenced not only by tissue at risk, but also by hormonal and inflammatory factors.