@article {7600, title = {Large meta-analysis of genome-wide association studies identifies five loci for lean body mass.}, journal = {Nat Commun}, volume = {8}, year = {2017}, month = {2017 Jul 19}, pages = {80}, abstract = {

Lean body mass, consisting mostly of skeletal muscle, is important for healthy aging. We performed a genome-wide association study for whole body (20 cohorts of European ancestry with n = 38,292) and appendicular (arms and legs) lean body mass (n = 28,330) measured using dual energy X-ray absorptiometry or bioelectrical impedance analysis, adjusted for sex, age, height, and fat mass. Twenty-one single-nucleotide polymorphisms were significantly associated with lean body mass either genome wide (p < 5 {\texttimes} 10-8) or suggestively genome wide (p < 2.3 {\texttimes} 10-6). Replication in 63,475 (47,227 of European ancestry) individuals from 33 cohorts for whole body lean body mass and in 45,090 (42,360 of European ancestry) subjects from 25 cohorts for appendicular lean body mass was successful for five single-nucleotide polymorphisms in/near HSD17B11, VCAN, ADAMTSL3, IRS1, and FTO for total lean body mass and for three single-nucleotide polymorphisms in/near VCAN, ADAMTSL3, and IRS1 for appendicular lean body mass. Our findings provide new insight into the genetics of lean body mass.Lean body mass is a highly heritable trait and is associated with various health conditions. Here, Kiel and colleagues perform a meta-analysis of genome-wide association studies for whole body lean body mass and find five novel genetic loci to be significantly associated.

}, issn = {2041-1723}, doi = {10.1038/s41467-017-00031-7}, author = {Zillikens, M Carola and Demissie, Serkalem and Hsu, Yi-Hsiang and Yerges-Armstrong, Laura M and Chou, Wen-Chi and Stolk, Lisette and Livshits, Gregory and Broer, Linda and Johnson, Toby and Koller, Daniel L and Kutalik, Zolt{\'a}n and Luan, Jian{\textquoteright}an and Malkin, Ida and Ried, Janina S and Smith, Albert V and Thorleifsson, Gudmar and Vandenput, Liesbeth and Hua Zhao, Jing and Zhang, Weihua and Aghdassi, Ali and {\r A}kesson, Kristina and Amin, Najaf and Baier, Leslie J and Barroso, In{\^e}s and Bennett, David A and Bertram, Lars and Biffar, Rainer and Bochud, Murielle and Boehnke, Michael and Borecki, Ingrid B and Buchman, Aron S and Byberg, Liisa and Campbell, Harry and Campos Obanda, Natalia and Cauley, Jane A and Cawthon, Peggy M and Cederberg, Henna and Chen, Zhao and Cho, Nam H and Jin Choi, Hyung and Claussnitzer, Melina and Collins, Francis and Cummings, Steven R and De Jager, Philip L and Demuth, Ilja and Dhonukshe-Rutten, Rosalie A M and Diatchenko, Luda and Eiriksdottir, Gudny and Enneman, Anke W and Erdos, Mike and Eriksson, Johan G and Eriksson, Joel and Estrada, Karol and Evans, Daniel S and Feitosa, Mary F and Fu, Mao and Garcia, Melissa and Gieger, Christian and Girke, Thomas and Glazer, Nicole L and Grallert, Harald and Grewal, Jagvir and Han, Bok-Ghee and Hanson, Robert L and Hayward, Caroline and Hofman, Albert and Hoffman, Eric P and Homuth, Georg and Hsueh, Wen-Chi and Hubal, Monica J and Hubbard, Alan and Huffman, Kim M and Husted, Lise B and Illig, Thomas and Ingelsson, Erik and Ittermann, Till and Jansson, John-Olov and Jordan, Joanne M and Jula, Antti and Karlsson, Magnus and Khaw, Kay-Tee and Kilpel{\"a}inen, Tuomas O and Klopp, Norman and Kloth, Jacqueline S L and Koistinen, Heikki A and Kraus, William E and Kritchevsky, Stephen and Kuulasmaa, Teemu and Kuusisto, Johanna and Laakso, Markku and Lahti, Jari and Lang, Thomas and Langdahl, Bente L and Launer, Lenore J and Lee, Jong-Young and Lerch, Markus M and Lewis, Joshua R and Lind, Lars and Lindgren, Cecilia and Liu, Yongmei and Liu, Tian and Liu, Youfang and Ljunggren, Osten and Lorentzon, Mattias and Luben, Robert N and Maixner, William and McGuigan, Fiona E and Medina-G{\'o}mez, Carolina and Meitinger, Thomas and Melhus, H{\r a}kan and Mellstr{\"o}m, Dan and Melov, Simon and Micha{\"e}lsson, Karl and Mitchell, Braxton D and Morris, Andrew P and Mosekilde, Leif and Newman, Anne and Nielson, Carrie M and O{\textquoteright}Connell, Jeffrey R and Oostra, Ben A and Orwoll, Eric S and Palotie, Aarno and Parker, Stephen C J and Peacock, Munro and Perola, Markus and Peters, Annette and Polasek, Ozren and Prince, Richard L and R{\"a}ikk{\"o}nen, Katri and Ralston, Stuart H and Ripatti, Samuli and Robbins, John A and Rotter, Jerome I and Rudan, Igor and Salomaa, Veikko and Satterfield, Suzanne and Schadt, Eric E and Schipf, Sabine and Scott, Laura and Sehmi, Joban and Shen, Jian and Soo Shin, Chan and Sigurdsson, Gunnar and Smith, Shad and Soranzo, Nicole and Stan{\v c}{\'a}kov{\'a}, Alena and Steinhagen-Thiessen, Elisabeth and Streeten, Elizabeth A and Styrkarsdottir, Unnur and Swart, Karin M A and Tan, Sian-Tsung and Tarnopolsky, Mark A and Thompson, Patricia and Thomson, Cynthia A and Thorsteinsdottir, Unnur and Tikkanen, Emmi and Tranah, Gregory J and Tuomilehto, Jaakko and van Schoor, Natasja M and Verma, Arjun and Vollenweider, Peter and V{\"o}lzke, Henry and Wactawski-Wende, Jean and Walker, Mark and Weedon, Michael N and Welch, Ryan and Wichmann, H-Erich and Widen, Elisabeth and Williams, Frances M K and Wilson, James F and Wright, Nicole C and Xie, Weijia and Yu, Lei and Zhou, Yanhua and Chambers, John C and D{\"o}ring, Angela and van Duijn, Cornelia M and Econs, Michael J and Gudnason, Vilmundur and Kooner, Jaspal S and Psaty, Bruce M and Spector, Timothy D and Stefansson, Kari and Rivadeneira, Fernando and Uitterlinden, Andr{\'e} G and Wareham, Nicholas J and Ossowski, Vicky and Waterworth, Dawn and Loos, Ruth J F and Karasik, David and Harris, Tamara B and Ohlsson, Claes and Kiel, Douglas P} } @article {7974, title = {Disentangling the genetics of lean mass.}, journal = {Am J Clin Nutr}, volume = {109}, year = {2019}, month = {2019 Feb 01}, pages = {276-287}, abstract = {

Background: Lean body mass (LM) plays an important role in mobility and metabolic function. We previously identified five loci associated with LM adjusted for fat mass in kilograms. Such an adjustment may reduce the power to identify genetic signals having an association with both lean mass and fat mass.

Objectives: To determine the impact of different fat mass adjustments on genetic architecture of LM and identify additional LM loci.

Methods: We performed genome-wide association analyses for whole-body LM (20 cohorts of European ancestry with n~=~38,292) measured using dual-energy X-ray absorptiometry) or bioelectrical impedance analysis, adjusted for sex, age, age2, and height with or without fat mass adjustments (Model 1 no fat adjustment; Model 2 adjustment for fat mass as a percentage of body mass; Model 3 adjustment for fat mass in kilograms).

Results: Seven single-nucleotide polymorphisms (SNPs) in separate loci, including one novel LM locus (TNRC6B), were successfully replicated in an additional 47,227 individuals from 29 cohorts. Based on the strengths of the associations in Model 1 vs Model 3, we divided the LM loci into those with an effect on both lean mass and fat mass in the same direction and refer to those as "sumo wrestler" loci (FTO and MC4R). In contrast, loci with an impact specifically on LM were termed "body builder" loci (VCAN and ADAMTSL3). Using existing available genome-wide association study databases, LM increasing alleles of SNPs in sumo wrestler loci were associated with an adverse metabolic profile, whereas LM increasing alleles of SNPs in "body builder" loci were associated with metabolic protection.

Conclusions: In conclusion, we identified one novel LM locus (TNRC6B). Our results suggest that a genetically determined increase in lean mass might exert either harmful or protective effects on metabolic traits, depending on its relation to fat mass.

}, issn = {1938-3207}, doi = {10.1093/ajcn/nqy272}, author = {Karasik, David and Zillikens, M Carola and Hsu, Yi-Hsiang and Aghdassi, Ali and {\r A}kesson, Kristina and Amin, Najaf and Barroso, In{\^e}s and Bennett, David A and Bertram, Lars and Bochud, Murielle and Borecki, Ingrid B and Broer, Linda and Buchman, Aron S and Byberg, Liisa and Campbell, Harry and Campos-Obando, Natalia and Cauley, Jane A and Cawthon, Peggy M and Chambers, John C and Chen, Zhao and Cho, Nam H and Choi, Hyung Jin and Chou, Wen-Chi and Cummings, Steven R and de Groot, Lisette C P G M and De Jager, Phillip L and Demuth, Ilja and Diatchenko, Luda and Econs, Michael J and Eiriksdottir, Gudny and Enneman, Anke W and Eriksson, Joel and Eriksson, Johan G and Estrada, Karol and Evans, Daniel S and Feitosa, Mary F and Fu, Mao and Gieger, Christian and Grallert, Harald and Gudnason, Vilmundur and Lenore, Launer J and Hayward, Caroline and Hofman, Albert and Homuth, Georg and Huffman, Kim M and Husted, Lise B and Illig, Thomas and Ingelsson, Erik and Ittermann, Till and Jansson, John-Olov and Johnson, Toby and Biffar, Reiner and Jordan, Joanne M and Jula, Antti and Karlsson, Magnus and Khaw, Kay-Tee and Kilpel{\"a}inen, Tuomas O and Klopp, Norman and Kloth, Jacqueline S L and Koller, Daniel L and Kooner, Jaspal S and Kraus, William E and Kritchevsky, Stephen and Kutalik, Zolt{\'a}n and Kuulasmaa, Teemu and Kuusisto, Johanna and Laakso, Markku and Lahti, Jari and Lang, Thomas and Langdahl, Bente L and Lerch, Markus M and Lewis, Joshua R and Lill, Christina and Lind, Lars and Lindgren, Cecilia and Liu, Yongmei and Livshits, Gregory and Ljunggren, Osten and Loos, Ruth J F and Lorentzon, Mattias and Luan, Jian{\textquoteright}an and Luben, Robert N and Malkin, Ida and McGuigan, Fiona E and Medina-G{\'o}mez, Carolina and Meitinger, Thomas and Melhus, H{\r a}kan and Mellstr{\"o}m, Dan and Micha{\"e}lsson, Karl and Mitchell, Braxton D and Morris, Andrew P and Mosekilde, Leif and Nethander, Maria and Newman, Anne B and O{\textquoteright}Connell, Jeffery R and Oostra, Ben A and Orwoll, Eric S and Palotie, Aarno and Peacock, Munro and Perola, Markus and Peters, Annette and Prince, Richard L and Psaty, Bruce M and R{\"a}ikk{\"o}nen, Katri and Ralston, Stuart H and Ripatti, Samuli and Rivadeneira, Fernando and Robbins, John A and Rotter, Jerome I and Rudan, Igor and Salomaa, Veikko and Satterfield, Suzanne and Schipf, Sabine and Shin, Chan Soo and Smith, Albert V and Smith, Shad B and Soranzo, Nicole and Spector, Timothy D and Stan{\v c}{\'a}kov{\'a}, Alena and Stefansson, Kari and Steinhagen-Thiessen, Elisabeth and Stolk, Lisette and Streeten, Elizabeth A and Styrkarsdottir, Unnur and Swart, Karin M A and Thompson, Patricia and Thomson, Cynthia A and Thorleifsson, Gudmar and Thorsteinsdottir, Unnur and Tikkanen, Emmi and Tranah, Gregory J and Uitterlinden, Andr{\'e} G and van Duijn, Cornelia M and van Schoor, Natasja M and Vandenput, Liesbeth and Vollenweider, Peter and V{\"o}lzke, Henry and Wactawski-Wende, Jean and Walker, Mark and J Wareham, Nicholas and Waterworth, Dawn and Weedon, Michael N and Wichmann, H-Erich and Widen, Elisabeth and Williams, Frances M K and Wilson, James F and Wright, Nicole C and Yerges-Armstrong, Laura M and Yu, Lei and Zhang, Weihua and Zhao, Jing Hua and Zhou, Yanhua and Nielson, Carrie M and Harris, Tamara B and Demissie, Serkalem and Kiel, Douglas P and Ohlsson, Claes} } @article {8377, title = {Putative Cut-Points in Sarcopenia Components and Incident Adverse Health Outcomes: An SDOC Analysis.}, journal = {J Am Geriatr Soc}, volume = {68}, year = {2020}, month = {2020 Jul}, pages = {1429-1437}, abstract = {

OBJECTIVES: Analyses performed by the Sarcopenia Definitions and Outcomes Consortium (SDOC) identified cut-points in several metrics of grip strength for consideration in a definition of sarcopenia. We describe the associations between the SDOC-identified metrics of low grip strength (absolute or standardized to body size/composition); low dual-energy x-ray absorptiometry (DXA) lean mass as previously defined in the literature (appendicular lean mass [ALM]/ht ); and slowness (walking speed <.8 m/s) with subsequent adverse outcomes (falls, hip fractures, mobility limitation, and mortality).

DESIGN: Individual-level, sex-stratified pooled analysis. We calculated odds ratios (ORs) or hazard ratios (HRs) for incident falls, mobility limitation, hip fractures, and mortality. Follow-up time ranged from 1 year for falls to 8.8 {\textpm} 2.3 years for mortality.

SETTING: Eight prospective observational cohort studies.

PARTICIPANTS: A total of 13,421 community-dwelling men and 4,828 community-dwelling women. MEASUREMENTS Grip strength by hand dynamometry, gait speed, and lean mass by DXA.

RESULTS: Low grip strength (absolute or standardized to body size/composition) was associated with incident outcomes, usually independently of slowness, in both men and women. ORs and HRs generally ranged from 1.2 to 3.0 for those below vs above the cut-point. DXA lean mass was not consistently associated with these outcomes. When considered together, those who had both muscle weakness by absolute grip strength (<35.5 kg in men and <20 kg in women) and slowness were consistently more likely to have a fall, hip fracture, mobility limitation, or die than those without either slowness or muscle weakness.

CONCLUSION: Older men and women with both muscle weakness and slowness have a higher likelihood of adverse health outcomes. These results support the inclusion of grip strength and walking speed as components in a summary definition of sarcopenia. J Am Geriatr Soc 68:1429-1437, 2020.

}, issn = {1532-5415}, doi = {10.1111/jgs.16517}, author = {Cawthon, Peggy M and Manini, Todd and Patel, Sheena M and Newman, Anne and Travison, Thomas and Kiel, Douglas P and Santanasto, Adam J and Ensrud, Kristine E and Xue, Qian-Li and Shardell, Michelle and Duchowny, Kate and Erlandson, Kristine M and Pencina, Karol M and Fielding, Roger A and Magaziner, Jay and Kwok, Timothy and Karlsson, Magnus and Ohlsson, Claes and Mellstr{\"o}m, Dan and Hirani, Vasant and Ribom, Eva and Correa-de-Araujo, Rosaly and Bhasin, Shalender} } @article {8989, title = {What Cut-Point in Gait Speed Best Discriminates Community-Dwelling Older Adults With Mobility Complaints From Those Without? A Pooled Analysis From the Sarcopenia Definitions and Outcomes Consortium.}, journal = {J Gerontol A Biol Sci Med Sci}, volume = {76}, year = {2021}, month = {2021 09 13}, pages = {e321-e327}, abstract = {

BACKGROUND: Cut-points to define slow walking speed have largely been derived from expert opinion.

METHODS: Study participants (13 589 men and 5043 women aged >=65years) had walking speed (m/s) measured over 4-6 m (mean {\textpm} SD: 1.20 {\textpm} 0.27 m/s in men and 0.94 {\textpm} 0.24 m/s in women.) Mobility limitation was defined as any self-reported difficulty with walking approximately 1/4 mile (prevalence: 12.6\% men, 26.4\% women). Sex-stratified classification and regression tree (CART) models with 10-fold cross-validation identified walking speed cut-points that optimally discriminated those who reported mobility limitation from those who did not.

RESULTS: Among 5043 women, CART analysis identified 2 cut-points, classifying 4144 (82.2\%) with walking speed >=0.75 m/s, which we labeled as "fast"; 478 (9.5\%) as "intermediate" (walking speed >=0.62 m/s but <0.75 m/s); and 421 (8.3\%) as "slow" (walking speed <0.62 m/s). Among 13 589 men, CART analysis identified 3 cut-points, classifying 10 001 (73.6\%) with walking speed >=1.00 m/s ("very fast"); 2901 (21.3\%) as "fast" (walking speed >=0.74 m/s but <1.00 m/s); 497 (3.7\%) as "intermediate" (walking speed >=0.57 m/s but <0.74 m/s); and 190 (1.4\%) as "slow" (walking speed <0.57 m/s). Prevalence of self-reported mobility limitation was lowest in the "fast" or "very fast" (11\% for men and 19\% for women) and highest in the "slow" (60.5\% in men and 71.0\% in women). Rounding the 2 slower cut-points to 0.60 m/s and 0.75 m/s reclassified very few participants.

CONCLUSIONS: Cut-points in walking speed of approximately 0.60 m/s and 0.75 m/s discriminate those with self-reported mobility limitation from those without.

}, keywords = {Aged, Female, Gait, Humans, Independent Living, Male, Mobility Limitation, Sarcopenia, Walking, Walking Speed}, issn = {1758-535X}, doi = {10.1093/gerona/glab183}, author = {Cawthon, Peggy M and Patel, Sheena M and Kritchevsky, Stephen B and Newman, Anne B and Santanasto, Adam and Kiel, Douglas P and Travison, Thomas G and Lane, Nancy and Cummings, Steven R and Orwoll, Eric S and Duchowny, Kate A and Kwok, Timothy and Hirani, Vasant and Schousboe, John and Karlsson, Magnus K and Mellstr{\"o}m, Dan and Ohlsson, Claes and Ljunggren, Osten and Xue, Qian-Li and Shardell, Michelle and Jordan, Joanne M and Pencina, Karol M and Fielding, Roger A and Magaziner, Jay and Correa-de-Araujo, Rosaly and Bhasin, Shalender and Manini, Todd M} } @article {9248, title = {Sex- and race-specific associations of bone mineral density with incident heart failure and its subtypes in older adults.}, journal = {J Am Geriatr Soc}, year = {2022}, month = {2022 Nov 05}, abstract = {

BACKGROUND: Previous studies have suggested an association between bone mineral density (BMD) and heart failure (HF) risk that may be race-dependent.

METHODS: We evaluated the relationship between BMD and incident HF in a cohort of older adults, the Health, Aging, and Body Composition (Health ABC) study (n~=~2835), and next performed a pooled analysis involving a second older cohort, the Cardiovascular Health Study (n~=~1268). Hip BMD was measured by dual-energy X-ray absorptiometry in both cohorts and spine BMD by computed tomography in a subset from Health ABC.

RESULTS: In Health ABC, lower BMD at the total hip was associated with higher incident HF in Black women after multivariable adjustment. Similar associations were found for BMD at the femoral neck and spine. In both cohorts, pooled analysis again revealed an association between lower total hip BMD and increased risk of HF in Black women (HR~=~1.41 per 0.1-g/cm decrement [95\% CI~=~1.23-1.62]), and showed the same to be true for White men (HR~=~1.12 [1.03-1.21]). There was a decreased risk of HF in Black men (HR 0.80 [0.70-0.91]), but no relationship in White women. The associations were numerically stronger with HFpEF for Black women and White men, and with HFrEF for Black men. Findings were similar for femoral neck BMD. Sensitivity analyses delaying HF follow-up by 2 years eliminated the association in Black men.

CONCLUSIONS: Lower BMD was associated with higher risk of HF and especially HFpEF in older Black women and White men, highlighting the need for additional investigation into underlying mechanisms.

}, issn = {1532-5415}, doi = {10.1111/jgs.18121}, author = {Gao, Hans and Patel, Sheena and Fohtung, Raymond B and Cawthon, Peggy M and Newman, Anne B and Cauley, Jane A and Carbone, Laura and Chaves, Paulo H M and Stein, Phyllis K and Civitelli, Roberto and Kizer, Jorge R} } @article {9481, title = {Circulating Growth Differentiation Factors 11 and 8, Their Antagonists Follistatin and Follistatin-like-3, and Risk of Heart Failure in Elders.}, journal = {J Gerontol A Biol Sci Med Sci}, year = {2023}, month = {2023 Aug 25}, abstract = {

BACKGROUND: Heterochronic parabiosis has identified growth differentiation factor (GDF)-11 as a potential means of cardiac rejuvenation, but findings have been inconsistent. A major barrier has been lack of assay specificity for GDF-11 and its homolog GDF-8.

METHODS: We tested the hypothesis that GDF-11 and GDF-8, and their major antagonists follistatin and follistatin-like (FSTL)-3, are associated with incident heart failure (HF) and its subtypes in elders. Based on validation experiments, we used liquid chromatography tandem mass spectrometry to measure total serum GDF-11 and GDF-8, along with follistatin and follistatin-like (FSTL)-3 by immunoassay, in two longitudinal cohorts of older adults.

RESULTS: In 2,599 participants (age 75.2{\textpm}4.3) followed for 10.8{\textpm}5.6 years, 721 HF events occurred. After adjustment, neither GDF-11 (HR per doubling: 0.93 [0.67, 1.30]) nor GDF-8 (HR: 1.02 per doubling [0.83, 1.27]) was associated with incident HF or its subtypes. Positive associations with HF were detected for follistatin (HR: 1.15 [1.00, 1.32]) and FLST-3 (HR: 1.38 [1.03, 1.85]), and with HF with preserved ejection fraction for FSTL-3 (HR: 1.77 [1.03, 3.02]). (All HRs per doubling of biomarker.) FSTL-3 associations with HF appeared stronger at higher follistatin levels and vice versa, and also for men, Blacks and lower kidney function.

CONCLUSIONS: Among older adults, serum follistatin and FSTL-3, but not GDF-11 or GDF-8, were associated with incident HF. These findings do not support the concept that low serum levels of total GDF-11 or GDF-8 contribute to HF late in life, but do implicate transforming growth factor-βsuperfamily pathways as potential therapeutic targets.

}, issn = {1758-535X}, doi = {10.1093/gerona/glad206}, author = {Kizer, Jorge R and Patel, Sheena and Ganz, Peter and Newman, Anne B and Bhasin, Shalender and Lee, Se-Jin and Cawthon, Peggy M and LeBrasseur, Nathan and Shah, Sanjiv J and Psaty, Bruce M and Tracy, Russell P and Cummings, Steven R} } @article {9487, title = {Factors Associated With Circulating Sex Hormones in Men : Individual Participant Data Meta-analyses.}, journal = {Ann Intern Med}, year = {2023}, month = {2023 Aug 29}, abstract = {

BACKGROUND: Various factors modulate circulating testosterone in men, affecting interpretation of testosterone measurements.

PURPOSE: To clarify factors associated with variations in sex hormone concentrations.

DATA SOURCES: Systematic literature searches (to July 2019).

STUDY SELECTION: Prospective cohort studies of community-dwelling men with total testosterone measured using mass spectrometry.

DATA EXTRACTION: Individual participant data (IPD) (9 studies; ~= 21 074) and aggregate data (2 studies; ~= 4075). Sociodemographic, lifestyle, and health factors and concentrations of total testosterone, sex hormone-binding globulin (SHBG), luteinizing hormone (LH), dihydrotestosterone, and estradiol were extracted.

DATA SYNTHESIS: Two-stage random-effects IPD meta-analyses found a nonlinear association of testosterone with age, with negligible change among men aged 17 to 70 years (change per SD increase about the midpoint, -0.27 nmol/L [-7.8 ng/dL] [CI, -0.71 to 0.18 nmol/L {-20.5 to 5.2 ng/dL}]) and decreasing testosterone levels with age for men older than 70 years (-1.55 nmol/L [-44.7 ng/dL] [CI, -2.05 to -1.06 nmol/L {-59.1 to -30.6 ng/dL}]). Testosterone was inversely associated with body mass index (BMI) (change per SD increase, -2.42 nmol/L [-69.7 ng/dL] [CI, -2.70 to -2.13 nmol/L {-77.8 to -61.4 ng/dL}]). Testosterone concentrations were lower for men who were married (mean difference, -0.57 nmol/L [-16.4 ng/dL] [CI, -0.89 to -0.26 nmol/L {-25.6 to -7.5 ng/dL}]); undertook at most 75 minutes of vigorous physical activity per week (-0.51 nmol/L [-14.7 ng/dL] [CI, -0.90 to -0.13 nmol/L {-25.9 to -3.7 ng/dL}]); were former smokers (-0.34 nmol/L [-9.8 ng/dL] [CI, -0.55 to -0.12 nmol/L {-15.9 to -3.5 ng/dL}]); or had hypertension (-0.53 nmol/L [-15.3 ng/dL] [CI, -0.82 to -0.24 nmol/L {-23.6 to -6.9 ng/dL}]), cardiovascular disease (-0.35 nmol/L [-10.1 ng/dL] [CI, -0.55 to -0.15 nmol/L {-15.9 to -4.3 ng/dL}]), cancer (-1.39 nmol/L [-40.1 ng/dL] [CI, -1.79 to -0.99 nmol/L {-51.6 to -28.5 ng/dL}]), or diabetes (-1.43 nmol/L [-41.2 ng/dL] [CI, -1.65 to -1.22 nmol/L {-47.6 to -35.2 ng/dL}]). Sex hormone-binding globulin was directly associated with age and inversely associated with BMI. Luteinizing hormone was directly associated with age in men older than 70 years.

LIMITATION: Cross-sectional analysis, heterogeneity between studies and in timing of blood sampling, and imputation for missing data.

CONCLUSION: Multiple factors are associated with variation in male testosterone, SHBG, and LH concentrations. Reduced testosterone and increased LH concentrations may indicate impaired testicular function after age 70 years. Interpretation of individual testosterone measurements should account particularly for age older than 70 years, obesity, diabetes, and cancer.

PRIMARY FUNDING SOURCE: Medical Research Future Fund, Government of Western Australia, and Lawley Pharmaceuticals. (PROSPERO: CRD42019139668).

}, issn = {1539-3704}, doi = {10.7326/M23-0342}, author = {Marriott, Ross J and Murray, Kevin and Adams, Robert J and Antonio, Leen and Ballantyne, Christie M and Bauer, Douglas C and Bhasin, Shalender and Biggs, Mary L and Cawthon, Peggy M and Couper, David J and Dobs, Adrian S and Flicker, Leon and Handelsman, David J and Hankey, Graeme J and Hannemann, Anke and Haring, Robin and Hsu, Benjumin and Karlsson, Magnus and Martin, Sean A and Matsumoto, Alvin M and Mellstr{\"o}m, Dan and Ohlsson, Claes and O{\textquoteright}Neill, Terence W and Orwoll, Eric S and Quartagno, Matteo and Shores, Molly M and Steveling, Antje and Tivesten, {\r A}sa and Travison, Thomas G and Vanderschueren, Dirk and Wittert, Gary A and Wu, Frederick C W and Yeap, Bu B} }