Red and White Blood Cell Counts Are Associated With Bone Marrow Adipose Tissue, Bone Mineral Density, and Bone Microarchitecture in Premenopausal Women.

Bone marrow adipose tissue (BMAT) resides within the bone marrow microenvironment where its function remains poorly understood. BMAT is elevated in anorexia nervosa, a disease model of chronic starvation, despite depletion of other fat depots. In addition to BMAT, the marrow microenvironment also consists of osteoblast and hematopoietic progenitors. BMAT is inversely associated with bone mineral density (BMD) in multiple populations including women with anorexia nervosa, and regulates hematopoiesis in animal models. We hypothesized that BMAT would be associated with circulating populations of hematopoietic cells (red and white blood cells) in humans and performed a post hoc analysis of two studies-a cross-sectional study and a longitudinal study-to investigate this hypothesis. We studied 89 premenopausal women cross-sectionally (median age [interquartile range], 27 [24.5, 31.7] years), including 35 with anorexia nervosa. We investigated associations between red blood cell (RBC) and white blood cell (WBC) counts and BMAT assessed by 1 H-magnetic resonance spectroscopy, BMD assessed by DXA, and bone microarchitecture assessed by HR-pQCT. In addition, we analyzed longitudinal data in six premenopausal women with anorexia nervosa treated with transdermal estrogen for 6 months and measured changes in BMAT and blood cell counts during treatment. Cross-sectionally, BMAT was inversely associated with WBC and RBC counts. In contrast, BMD and parameters of bone microarchitecture were positively associated with WBC and RBC. In women with anorexia nervosa treated with transdermal estrogen for 6 months, decreases in BMAT were significantly associated with increases in both RBC and hematocrit (rho = -0.83, p = 0.04 for both). In conclusion, we show that BMAT is inversely associated with WBC and RBC in premenopausal women, and there is a potential association between longitudinal changes in BMAT and changes in RBC. These associations warrant further study and may provide further insight into the role and function of this understudied adipose depot. © 2020 American Society for Bone and Mineral Research.

Neuroactive Steroids and Affective Symptoms in Women Across the Weight Spectrum.

3α-5α-Tetrahydroprogesterone, a progesterone metabolite also known as allopregnanolone, and 5α-androstane-3α,17ß-diol, a testosterone metabolite also known as 3α-androstanediol, are neuroactive steroids and positive GABAA receptor allosteric modulators. Both anorexia nervosa (AN) and obesity are complicated by affective comorbidities and hypothalamic-pituitary-gonadal dysregulation. However, it is not known whether neuroactive steroid levels are abnormal at the extremes of the weight spectrum. We hypothesized that serum allopregnanolone and 3α-androstanediol levels would be decreased in AN compared with healthy controls (HC) and negatively associated with affective symptoms throughout the weight spectrum, independent of body mass index (BMI). Thirty-six women were 1 : 1 age-matched across three groups: AN, HC, and overweight/obese (OW/OB). AN were amenorrheic; HC and OW/OB were studied in the follicular phase. Fasting serum neuroactive steroids were measured by gas chromatography/mass spectrometry. Mean Hamilton depression and anxiety scores were highest in AN (p<0.0001). Mean serum allopregnanolone was lower in AN and OW/OB than HC (AN 95.3±56.4 vs OW/OB 73.8±31.3 vs HC 199.5±167.8 pg/ml, p=0.01), despite comparable mean serum progesterone. Allopregnanolone levels, but not progesterone levels, were negatively associated with depression and anxiety symptom severity, independent of BMI. Serum 3α-androstanediol levels did not differ among groups and were not associated with depression or anxiety scores, despite a significant negative association between free testosterone levels and both anxiety and depression severity. In conclusion, women at both extremes of the weight spectrum have low mean serum allopregnanolone, which is associated with increased depression and anxiety severity, independent of BMI. Neuroactive steroids such as allopregnanolone may be potential therapeutic targets for depression and anxiety in traditionally treatment-resistant groups, including AN.

Plasma sodium level is associated with bone loss severity in women with anorexia nervosa: a cross-sectional study.

BACKGROUND: Anorexia nervosa is a psychiatric disorder characterized by restrictive eating, low body weight, and severe bone loss. Recent data show a deleterious relationship between low circulating sodium levels and bone mass, and relative or absolute hyponatremia is a known complication of anorexia nervosa. Clinical studies of other medical conditions associated with hyponatremia suggest that detrimental effects of low sodium levels on health are seen even within the normal range. We hypothesized that women with anorexia nervosa and relatively low plasma sodium levels would have lower bone mineral density (BMD) than those with higher plasma sodium levels. METHOD: In a cross-sectional study (January 1, 1997-December 31, 2009) of 404 women aged 17 to 54 years (mean ± standard error of the mean [SEM] age = 25.6 ± 0.3 years) who met DSM-IV criteria for anorexia nervosa, we measured BMD using dual-energy x-ray absorptiometry. Bone mineral density was compared in women with plasma sodium levels < 140 mmol/L (midpoint of normal range) versus those with plasma sodium levels ≥ 140 mmol/L and in women with hyponatremia (plasma sodium < 135 mmol/L) versus those without. The study was conducted at the Neuroendocrine Unit of Massachusetts General Hospital, Boston. RESULTS: Women with plasma sodium levels < 140 mmol/L had significantly lower BMD and t and z scores versus those with plasma sodium levels ≥ 140 mmol/L at the anterior-posterior (AP) spine (mean ± SEM z scores = -1.6 ± 0.1 vs -1.3 ± 0.1, P = .004) and total hip (mean ± SEM z scores = -1.2 ± 0.1 vs -0.9 ± 0.1, P = .029). In a model controlling for age, BMI, psychiatric drug use, and disease duration, differences in BMD and t and z scores remained significant at the AP spine. Women with hyponatremia had significantly lower BMD and t and z scores versus those without hyponatremia at the AP spine (mean ± SEM z scores = -2.2 ± 0.3 vs -1.3 ± 0.1, P = .009), lateral spine (mean ± SEM z scores = -2.4 ± 0.4 vs -1.5 ± 0.1, P = .031), and total hip (mean ± SEM z scores = -2.5 ± 0.5 vs -1.0 ± 0.1, P < .0001). In a model controlling for age, BMI, psychiatric drug use, and disease duration, differences in BMD and z and t scores remained significant at all sites. CONCLUSIONS: These data suggest that relative plasma sodium deficiency may contribute to anorexia nervosa-related osteopenia.

Marrow fat and preadipocyte factor-1 levels decrease with recovery in women with anorexia nervosa.

Women with anorexia nervosa (AN) have elevated marrow fat mass despite low visceral and subcutaneous fat depots, which is inversely associated with bone mineral density (BMD). Whether marrow fat mass remains persistently elevated or decreases with recovery from AN is currently unknown. In this study, we investigated changes in marrow fat in women who have recovered from AN (AN-R). We also studied the relationship between preadipocyte factor (Pref)-1-a member of the EGF-like family of proteins and regulator of adipocyte and osteoblast differentiation-and fat depots and BMD in AN-R compared with women with AN and healthy controls (HC). We studied 29 women: 14 with active or recovered AN (30.7 + 2.2 years [mean ± SEM]) and 15 normal-weight controls (27.8 ± 1.2 years). We measured marrow adipose tissue (MAT) of the L4 vertebra and femur by (1) H-magnetic resonance spectroscopy; BMD of the spine, hip, and total body by DXA; and serum Pref-1 and leptin levels. We found that MAT of the L4 vertebra was significantly lower in AN-R compared with AN (p = 0.03) and was comparable to levels in HC. Pref-1 levels were also significantly lower in AN-R compared with AN (p = 0.02) and comparable to levels in healthy controls. Although Pref-1 was positively associated with MAT of the L4 vertebra in AN (R = 0.94; p = 0.002), we found that it was inversely associated with MAT of the L4 vertebra in HC (R = -0.71; p = 0.004). Therefore, we have shown that MAT and Pref-1 levels decrease with recovery from AN. Our data suggest that Pref-1 may have differential effects in states of nutritional deprivation compared with nutritional sufficiency.

Effects of risedronate and low-dose transdermal testosterone on bone mineral density in women with anorexia nervosa: a randomized, placebo-controlled study.

CONTEXT: Anorexia nervosa is complicated by severe bone loss and clinical fractures. Mechanisms underlying bone loss in adults with anorexia nervosa include increased bone resorption and decreased formation. Estrogen administration has not been shown to prevent bone loss in this population, and to date, there are no approved, effective therapies for this comorbidity. OBJECTIVE: To determine whether antiresorptive therapy with a bisphosphonate alone or in combination with low-dose transdermal testosterone replacement would increase bone mineral density (BMD) in women with anorexia nervosa. DESIGN AND SETTING: We conducted a12-month, randomized, placebo-controlled study at a clinical research center. STUDY PARTICIPANTS: Participants included 77 ambulatory women with anorexia nervosa. INTERVENTION: Subjects were randomized to risedronate 35 mg weekly, low-dose transdermal testosterone replacement therapy, combination therapy or double placebo. MAIN OUTCOME MEASURES: BMD at the spine (primary endpoint), hip, and radius and body composition were measured by dual-energy x-ray absorptiometry. RESULTS: Risedronate increased posteroanterior spine BMD 3%, lateral spine BMD 4%, and hip BMD 2% in women with anorexia nervosa compared with placebo in a 12-month clinical trial. Testosterone administration did not improve BMD but increased lean body mass. There were few side effects associated with either therapy. CONCLUSIONS: Risedronate administration for 1 yr increased spinal BMD, the primary site of bone loss in women with anorexia nervosa. Low-dose testosterone did not change BMD but increased lean body mass.

Hormone predictors of abnormal bone microarchitecture in women with anorexia nervosa.

Osteopenia is a complication of anorexia nervosa (AN) associated with a two- to three-fold increase in fractures. Nutritional deficits and hormonal abnormalities are thought to mediate AN-induced bone loss. Alterations in bone microarchitecture may explain fracture risk independent of bone mineral density (BMD). Advances in CT imaging now allow for noninvasive evaluation of trabecular microstructure at peripheral sites in vivo. Few data are available regarding bone microarchitecture in AN. We therefore performed a cross-sectional study of 23 women (12 with AN and 11 healthy controls) to determine hormonal predictors of trabecular bone microarchitecture. Outcome measures included bone microarchitectural parameters at the ultradistal radius by flat-panel volume CT (fpVCT); BMD at the PA and lateral spine, total hip, femoral neck, and ultradistal radius by dual energy X-ray absorptiometry (DXA); and IGF-I, leptin, estradiol, testosterone, and free testosterone levels. Bone microarchitectural measures, including apparent (app.) bone volume fraction, app. trabecular thickness, and app. trabecular number, were reduced (p<0.03) and app. trabecular spacing was increased (p=0.02) in AN versus controls. Decreased structural integrity at the ultradistal radius was associated with decreased BMD at all sites (p

Reduced amylin levels are associated with low bone mineral density in women with anorexia nervosa.

CONTEXT: Anorexia nervosa, characterized by extreme low body weight due to reduced nutrient intake, is associated with severe bone loss. Peptide hormones, including amylin, GIP, and GLP2, are released immediately after nutrient intake and may be involved in the regulation of bone turnover. OBJECTIVE: To investigate fasting levels of amylin, GIP, and GLP2 and their relationships with bone mineral density (BMD) in women with anorexia nervosa compared to healthy controls. DESIGN: Cross-sectional. SETTING: Clinical Research Center. STUDY PARTICIPANTS: 15 women with anorexia nervosa and 16 healthy controls. INTERVENTION: None. MAIN OUTCOME MEASURES: Fasting serum amylin, GIP, and GLP2, and BMD. RESULTS: Women with anorexia nervosa had significantly lower fasting serum amylin and GIP levels than healthy controls. Fasting serum GLP2 levels were not significantly different between groups. Fasting amylin levels were positively associated with BMD and Z-score at the PA spine, total hip, and femoral neck. Fasting amylin levels were also positively associated with weight and percent fat; after controlling for these variables, amylin was still a significant predictor of BMD and Z-score at the femoral neck and of Z-score at the total hip. In the anorexia nervosa group, there was a trend toward an inverse association between amylin and C-terminal telopeptide (CTX) levels (R=-0.47, p=0.08). GIP and GLP2 levels did not predict BMD at any site. CONCLUSION: Decreased secretion of amylin may be a mechanism through which reduced nutrient intake adversely affects BMD in anorexia nervosa.

Preadipocyte factor-1 is associated with marrow adiposity and bone mineral density in women with anorexia nervosa.

CONTEXT: Despite having low visceral and sc fat depots, women with anorexia nervosa (AN) have elevated marrow fat mass, which is inversely associated with bone mineral density (BMD). Adipocytes and osteoblasts differentiate from a common progenitor cell, the human mesenchymal stem cell. Therefore, understanding factors that regulate this differentiation process may provide insight into bone loss in AN. OBJECTIVE: The objective of the study was to investigate the relationship between preadipocyte factor-1 (Pref-1), a member of the epidermal growth factor-like family of proteins and regulator of adipocyte and osteoblast differentiation, and fat depots and BMD in AN. DESIGN: This was a cross-sectional study. SETTING: The study was conducted at a clinical research center. PATIENTS: Patients included 20 women with AN (26.8 +/- 1.5 yr) and 10 normal-weight controls (29.2 +/- 1.7 yr). INTERVENTIONS: There were no interventions. MAIN OUTCOMES MEASURE: Pref-1, leptin, IGF-I, IGF binding protein (IGF-BP)-2 and estradiol levels were measured. BMD of the spine and hip was measured by dual-energy x-ray absorptiometry. Marrow fat content of the L4 vertebra and femur was measured by (1)H-magnetic resonance spectroscopy. RESULTS: Pref-1 levels were significantly higher in AN compared with controls (P = 0.01). There was a positive correlation between Pref-1 and marrow fat of the proximal femoral metaphysis (R = 0.50, P = 0.01) and an inverse association between leptin and L4 marrow fat (R = -0.45, P < 0.05). There was an inverse association between Pref-1 and BMD of both the anteroposterior spine and lateral spine (R = -0.54, P = 0.003; R = -0.44, P = 0.02, respectively). CONCLUSIONS: Pref-1 is elevated in AN. Pref-1, IGF-I, IGF-BP2 and leptin are associated with marrow adiposity and BMD.

Hypercortisolemia is associated with severity of bone loss and depression in hypothalamic amenorrhea and anorexia nervosa.

CONTEXT: Anorexia nervosa (AN) and functional hypothalamic amenorrhea (HA) are associated with low bone density, anxiety, and depression. Women with AN and HA have elevated cortisol levels. Significant hypercortisolemia, as in Cushing's disease, causes bone loss. It is unknown whether anxiety and depression and/or cortisol dysregulation contribute to low bone density in AN or HA. OBJECTIVE: Our objective was to investigate whether hypercortisolemia is associated with bone loss and mood disturbance in women with HA and AN. DESIGN AND SETTING: We conducted a cross-sectional study in a clinical research center. PARTICIPANTS: We studied 52 women [21 healthy controls (HC), 13 normal-weight women with functional HA, and 18 amenorrheic women with AN]. OUTCOME MEASURES: Serum samples were measured every 20 min for 12 h overnight and pooled for average cortisol levels. Bone mineral density (BMD) was assessed by dual-energy x-ray absorptiometry (DXA) at anteroposterior and lateral spine and hip. Hamilton Rating Scales for Anxiety (HAM-A) and Depression (HAM-D) were administered. RESULTS: BMD was lower in AN and HA than HC at all sites and lower in AN than HA at the spine. On the HAM-D and HAM-A, AN scored higher than HA, and HA scored higher than HC. Cortisol levels were highest in AN, intermediate in HA, and lowest in HC. HAM-A and HAM-D scores were associated with decreased BMD. Cortisol levels were positively associated with HAM-A and HAM-D scores and negatively associated with BMD. CONCLUSIONS: Hypercortisolemia is a potential mediator of bone loss and mood disturbance in these disorders.

Hormonal and nutritional effects on cardiovascular risk markers in young women.

CONTEXT: Cardiovascular (CV) risk markers, including high-sensitivity C-reactive protein (hsCRP), are increasingly important in predicting cardiac events. A favorable CV risk profile might be expected in anorexia nervosa (AN) due to low body weight and dietary fat intake. However, women with AN have decreased IGF-I levels reflecting decreased GH action, and IGF-I deficiency is associated with elevated hsCRP. Moreover, oral estrogens, known to increase hsCRP in other populations, are commonly prescribed in AN. To date, hsCRP levels and their physiological determinants have not been reported in women with AN. OBJECTIVE: We examined the relationship between CV risk markers, undernutrition, IGF-I, and oral estrogens, specifically hypothesizing that in the setting of undernutrition, AN would be associated with low hsCRP despite low IGF-I levels and that those women taking oral contraceptive pills (OCPs) would have higher hsCRP and lower IGF-I levels. DESIGN AND SETTING: We conducted a cross-sectional study at a clinical research center. STUDY PARTICIPANTS: Subjects included 181 women: 140 women with AN [85 not receiving OCPs (AN-E) and 55 receiving OCPs (AN+E)] and 41 healthy controls [28 not receiving OCPs (HC-E) and 13 receiving OCPs (HC+E)]. MAIN OUTCOME MEASURES: We assessed hsCRP, IL-6, IGF-I, low-density lipoprotein (LDL), and high-density lipoprotein (HDL). RESULTS: Despite low weight, more than 20% of AN+E had high-risk hsCRP levels. AN+E had higher hsCRP than AN-E. AN-E had lower mean hsCRP levels than healthy controls (HC+E and HC-E). IL-6 levels were higher in AN+E with elevated hsCRP (>3 mg/liter) than in AN+E with normal hsCRP levels. IGF-I was inversely associated with hsCRP in healthy women, suggesting a protective effect of GH on CV risk. However, this was not seen in AN. Few patients in any group had high-risk LDL or HDL levels. CONCLUSIONS: Although hsCRP levels are lower in AN than healthy controls, OCP use puts such women at a greater than 20% chance of having hsCRP in the high-CV-risk (>3 mg/liter) category. The elevated mean IL-6 in women with AN and high-risk hsCRP levels suggests that increased systemic inflammation may underlie the hsCRP elevation in these patients. Although OCP use in AN was associated with slightly lower mean LDL and higher mean HDL, means were within the normal range, and few patients in any group had high-risk LDL or HDL levels. IGF-I levels appear to be important determinants of hsCRP in healthy young women. In contrast, IGF-I does not appear to mediate hsCRP levels in AN.