Profile of Persons Recently Infected with HIV-1 in Belgium: New Insights to Tailor Prevention Efforts.

Despite wide availability of prevention and treatment services, including the ongoing roll-out of pre-exposure prophylaxis (PrEP), the HIV epidemic is not under control in Belgium. Hence, there is a recognized need to improve case finding and early diagnosis to curb the further spread of HIV more effectively. The objective of the present study was to improve insight into the profiles of persons recently infected with HIV-1 and on their prevention trajectory. Between May 2018 and December 2022, we selected persons diagnosed in Belgium within three months of the presumed infection date. We then analyzed information collected using a questionnaire covering topics on HIV testing, sexually transmitted infections (STIs), PrEP use, sexual behavior, partner notification and substance use. The data obtained were analyzed alongside information derived from phylogenetic cluster analysis of the viral source of infection. A total of 93 persons with a recent HIV-1 infection completed the questionnaire, the majority (74%) being MSM, 14% were heterosexual women and 12% were heterosexual men. Nearly one-third of participants engaged in sexual activity with an average of 2 to 5 casual partners around the presumed time of infection. A significant percentage reported frequent substance use during sexual activity (65%), being previously diagnosed with STI (65%) and using condoms infrequently (44%). 63% reported a testing frequency of at least one HIV test per year before being diagnosed and 46% notified their previous sex partner(s) after being diagnosed. Over 20% of respondents (including 11 MSM, 4 heterosexual men and 5 heterosexual women) reported exclusive sexual activity with their steady partner. Eight participants (9%, all MSM, 75% born outside of Belgium) reported PrEP use in the past. No significant differences in behavioral characteristics were found between persons who were part of a local transmission cluster (48%) and persons that were not part of a cluster (47%). The study results revealed that the majority of persons diagnosed early with HIV-1 infection in Belgium exhibited characteristics corresponding to a high-at-risk population and were aware of this risk, as evidenced by a high testing frequency. However, partner notification rates were low and use and awareness of PrEP limited. A notable group of persons not corresponding to the high-risk profiles was also identified. This information may help to expose missed opportunities for prevention and contribute to enhancing the implementation of future prevention measures.

Randomized trial: treatment of genitourinary syndrome of menopause using radiofrequency.

OBJECTIVE: A randomized controlled study was conducted to evaluate the safety and efficacy of radiofrequency treatment in postmenopausal women not willing to use or presenting a contraindication for menopause hormone therapy (MHT) and suffering from genitourinary syndrome of menopause (GSM). METHODS: A prospective randomized open study evaluated the effect of radiofrequency treatment versus a gel (control group) in postmenopausal women suffering from GSM. Patients were assessed at baseline and after 10-12 weeks of treatment for severity of vulvovaginal atrophy, dyspareunia, pH, vaginal smear maturation index, Vaginal Health Index and Female Sexual Function Index. The difference at baseline and after 10-12 weeks of treatment and the difference in improvement were tested between groups by a two-sample t-test and the Mann-Whitney test. RESULTS: Due to the COVID-19 pandemic, we were only able to treat 48 patients (24 patients using radiofrequency and 24 patients using a gel). Globally, at the end of the study, there were no differences in changes of the measured outcomes between the group of women treated with radiofrequency and the control group. CONCLUSION: Radiofrequency treatment was found to be safe, but was not superior to a gel, although the study lacked power. The study was registered at ClinicalTrials.gov (NCT03857893).

Determining clinically important differences in health-related quality of life in older patients with cancer undergoing chemotherapy or surgery.

PURPOSE: Using the EORTC Global Health Status (GHS) scale, we aimed to determine minimal clinically important differences (MCID) in health-related quality of life (HRQOL) changes for older cancer patients with a geriatric risk profile, as defined by the geriatric 8 (G8) health screening tool, undergoing treatment. Simultaneously, we assessed baseline patient characteristics prognostic for HRQOL changes. METHODS: Our analysis included 1424 (G8 ≤ 14) older patients with cancer scheduled to receive chemotherapy (n = 683) or surgery (n = 741). Anchor-based methods, linking the GHS score to clinical indicators, were used to determine MCID between baseline and follow-up at 3 months. A threshold of 0.2 standard deviation (SD) was used to exclude MCID estimates too small for interpretation. Logistic regressions analysed baseline patient characteristics prognostic for HRQOL changes. RESULTS: The 15-item Geriatric Depression Scale (GDS15), Visual Analogue Scale (VAS) for Fatigue and ECOG Performance Status (PS) were selected as clinical anchors. In the surgery group, MCID estimates for improvement and deterioration were ECOG PS (5*, 11*), GDS15 (5*, 2) and VAS Fatigue (3, 9*). In the chemotherapy group, MCID estimates for improvement and deterioration were ECOG PS (8*, 7*), GDS15 (5, 4) and VAS Fatigue (5, 5*). Estimates with * were > 0.2 SD threshold. Patients experiencing pain or malnutrition (surgery group) or fatigue (chemotherapy group) at baseline showed a significantly stable or improved HRQOL (p < 0.05) after their treatment. CONCLUSION: The reported MCID for improvement and deterioration depended on the anchor used and treatment received. The estimates can be used to evaluate significant changes in HRQOL and to determine sample sizes in clinical trials.

Adherence to geriatric assessment-based recommendations in older patients with cancer: a multicenter prospective cohort study in Belgium.

Background: In the general older population, geriatric assessment (GA)-guided treatment plans can improve overall survival, quality of life and functional status (FS). In GA-related research in geriatric oncology, studies mainly focused on geriatric screening and GA but not on geriatric recommendations, interventions and follow-up. The aim of this study was to investigate the adherence to geriatric recommendations and subsequent actions undertaken in older patients with cancer. Patient and methods: A prospective Belgian multicenter (N = 22) cohort study included patients ≥70 years with a malignant tumor upon oncologic treatment decision. Patients with an abnormal result on the geriatric screening (G8 ≤14/17) underwent GA. Geriatric recommendations were formulated based on GA results. At follow-up the adherence to geriatric recommendations was documented including a description of actions undertaken. Results: From November 2012 till February 2015, G8 screening was carried out in 8451 patients, of which 5838 patients had an abnormal result. Geriatric recommendations data were available for 5631 patients. Geriatric recommendations were made for 4459 patients. Geriatric interventions data were available for 4167 patients. A total of 12 384 geriatric recommendations were made. At least one different geriatric recommendation was implemented in 2874 patients. A dietician, social worker and geriatrician intervened most frequently for problems detected on the nutritional, social and functional domain. A total of 7569 actions were undertaken for a total of 5725 geriatric interventions, most frequently nutritional support and supplements, extended home care and psychological support. Conclusions: This large-scale Belgian study focuses on the adherence to geriatric recommendations and subsequent actions undertaken and contributes to the optimal management of older patients with cancer. We identified the domains for which geriatric recommendations are most frequently made and adhered to, and which referrals to other health care workers and facilities are frequently applied in the multidisciplinary approach of older patients with cancer.

[A rare case of hepatotoxicity in geriatrics]. / Un cas rare d'hépatotoxicité en gériatrie.

We report a case of hepatotoxicity following the introduction of two drugs to treat a 81 years old man. The presence of liver alterations following the introduction of a new drug must suggest an adverse drug reaction. Manifestations of adverse drug reactions are often non-specific. Thus, the most important problem in assessing adverse drug reactions is establishing whether there is a causal association between the suspected drug and the untoward clinical event. The use of the Naranjo score could help the clinician to assess the probability of a causal relationship between a drug and the suspected adverse drug reaction.

Nous présentons le cas d'un patient de 81 ans qui développe une hépatotoxité après l'introduction de deux médicaments dans son traitement. La présence d'une perturbation du bilan hépatique à l'introduction d'un nouveau médicament doit faire évoquer une hépatotoxicité médicamenteuse. Les manifestations des effets secondaires médicamenteux ne sont généralement pas spécifiques. Dans ce contexte, le problème le plus important pour le clinicien est d'établir la probabilité d'une relation causale entre l'effet et le médicament suspecté. Le calcul du score de Naranjo permet d'aider le clinicien dans l'évaluation de la probabilité d'une relation causale entre un médicament et la suspicion de l'apparition d'un effet secondaire.

Diffusion kurtosis imaging probes cortical alterations and white matter pathology following cuprizone induced demyelination and spontaneous remyelination.

Although MRI is the gold standard for the diagnosis and monitoring of multiple sclerosis (MS), current conventional MRI techniques often fail to detect cortical alterations and provide little information about gliosis, axonal damage and myelin status of lesioned areas. Diffusion tensor imaging (DTI) and diffusion kurtosis imaging (DKI) provide sensitive and complementary measures of the neural tissue microstructure. Additionally, specific white matter tract integrity (WMTI) metrics modelling the diffusion in white matter were recently derived. In the current study we used the well-characterized cuprizone mouse model of central nervous system demyelination to assess the temporal evolution of diffusion tensor (DT), diffusion kurtosis tensor (DK) and WMTI-derived metrics following acute inflammatory demyelination and spontaneous remyelination. While DT-derived metrics were unable to detect cuprizone induced cortical alterations, the mean kurtosis (MK) and radial kurtosis (RK) were found decreased under cuprizone administration, as compared to age-matched controls, in both the motor and somatosensory cortices. The MK remained decreased in the motor cortices at the end of the recovery period, reflecting long lasting impairment of myelination. In white matter, DT, DK and WMTI-derived metrics enabled the detection of cuprizone induced changes differentially according to the stage and the severity of the lesion. More specifically, the MK, the RK and the axonal water fraction (AWF) were the most sensitive for the detection of cuprizone induced changes in the genu of the corpus callosum, a region less affected by cuprizone administration. Additionally, microgliosis was associated with an increase of MK and RK during the acute inflammatory demyelination phase. In regions undergoing severe demyelination, namely the body and splenium of the corpus callosum, DT-derived metrics, notably the mean diffusion (MD) and radial diffusion (RD), were among the best discriminators between cuprizone and control groups, hence highlighting their ability to detect both acute and long lasting changes. Interestingly, WMTI-derived metrics showed the aptitude to distinguish between the different stages of the disease. Both the intra-axonal diffusivity (Da) and the AWF were found to be decreased in the cuprizone treated group, Da specifically decreased during the acute inflammatory demyelinating phase whereas the AWF decrease was associated to the spontaneous remyelination and the recovery period. Altogether our results demonstrate that DKI is sensitive to alterations of cortical areas and provides, along with WMTI metrics, information that is complementary to DT-derived metrics for the characterization of demyelination in both white and grey matter and subsequent inflammatory processes associated with a demyelinating event.

[Appropriate use of psychotropic drugs in institutionalized elderly presenting acute confusional state (delirium)]. / Usage adéquat des psychotropes chez les personnes âgées institutionnalisées en cas d'état confusionnel aigu (delirium).

Delirium (acute confusion) is a common, morbid, and costly geriatric syndrome that affects onethird of hospitalized older adults. As evidence mounts that delirium may persist for weeks to months, concern about delirium can no longer be restricted to acute hospitals. We present a review about non-pharmacologic and pharmacologic management of delirium in institution.

Le " Delirium " (état confusionnel) est un syndrome gériatrique fréquent et coûteux qui affecte un tiers des personnes âgées hospitalisées ; sa prévalence en institution est mal connue. Il apparaît que ce syndrome peut persister pendant des semaines à des mois, et n'est donc pas limité aux hospitalisations aiguës. Nous présentons une revue de la littérature sur la prise en charge du delirium en institution suivie d'une proposition d'algorithme définissant l'approche pharmacologique et non pharmacologique de ce syndrome gériatrique.

Rituximab in diffuse cutaneous systemic sclerosis: an open-label clinical and histopathological study.

OBJECTIVES: The safety and potential efficacy of rituximab was examined in diffuse cutaneous systemic sclerosis (dc-SSc). METHODS: A 24 week open-label study in which eight patients with dc-SSc received an infusion of 1000 mg rituximab administered at baseline and day 15, together with 100 mg methylprednisolone at each infusion. Assessment included CD19+ peripheral blood lymphocyte number, skin sclerosis score, indices of internal organ functioning, the health assessment questionnaire disability index, the 36-item Short Form health survey and histopathological evaluation of the skin. RESULTS: Ritixumab induced effective B-cell depletion in all patients (<5 CD19+ cells/microl blood). There was a significant change in skin score at week 24 (p<0.001). Also, significant improvements were measured in the dermal hyalinised collagen content (p = 0.014) and dermal myofibroblast numbers (p = 0.011). Two serious adverse events occurred, which were thought to be unrelated to the rituximab treatment. CONCLUSIONS: Rituximab appears to be well tolerated and may have potential efficacy for skin disease in dc-SSc.

Validation of a new screening strategy for anti-extractable nuclear antigen antibodies.

OBJECTIVE: Although indirect immunofluorescence (IIF) is the most widely applied screening test for antinuclear antibodies (ANA), it lacks specificity for the identification of specific diseases or antigen reactivities. The aim of the present study was to validate an anti-extractable nuclear antigen (ENA) screening strategy encompassing a three-step cascade whereby an ELISA with pooled specific ENA is positioned between the IIF and the final anti-ENA identification. METHODS: Sera from 4 populations were tested for anti-ENA using an automated ELISA (EliA Symphony) and a line immunoassay (INNO-LIA ANA update). RESULTS: At the manufacturer's cut-off, a 96% sensitivity (95% CI 94%-98%) and 96% specificity (95% CI 94%-98%) of EliA Symphony for anti-ENA was obtained in a consecutive selection of 328 IIF positive serum samples referred for ANA testing. In addition, a high sensitivity was demonstrated for anti-ENA reactivities in patients with SLE (99%, 95% CI 97%-101%) and SSc (100%), and for anti-ENA monoreactivities. CONCLUSION: The EliA Symphony test was shown to be a sensitive second-line screening test for anti-ENA antibodies. In the context of a high clinical suspicion of connective tissue disease or autoreactivities not included in the EliA Symphony assay, third-line testing may be useful, even if the anti-ENA screening is negative.

Over-representation of construction-related occupations in male patients with systemic sclerosis.

AIMS: Based on preliminary observations, we tested the hypothesis that construction-related occupations are associated with systemic sclerosis (SSc). METHODS: The professional occupation of 91 patients with SSc (71 females and 20 males) was recorded. Categorisation into construction-related and other professions was performed. A double definition was used for construction-related occupations. The first (limited) definition was based upon categories of the Belgian National Institute of Statistics (NIS) occupational list. The following occupations were considered construction-related: electricians, joiners, masons and tilers, plumbers and pipefitters. The use of this list also allows us to compare the distribution of professions in these patients with that in the general population. As the NIS occupational list is limitative and leaves out some "real-life" construction-related occupations, a second and broader interpretation was given to the concept of construction-related occupations. RESULTS: The prevalence of construction-related professions in males with SSc, according to the limited definition, was 10-fold higher than in the general working population (50% vs 5%; p<0.001). Interestingly, most of the patients with construction-related occupations were electricians. In the broader interpretation, 75% of the men with SSc fell into the category of construction-related occupations. CONCLUSIONS: The data show an association between SSc and professional occupation.

Do all anti-citrullinated protein/peptide antibody tests measure the same? Evaluation of discrepancy between anti-citrullinated protein/peptide antibody tests in patients with and without rheumatoid arthritis.

BACKGROUND: Different methods exist to demonstrate anti-citrullinated protein/peptide antibodies (ACPA). AIMS: To evaluate discrepancy between four ACPA tests. PATIENTS AND METHODS: Population 1 consisted of patients with a new diagnostic problem, including 86 patients with rheumatoid arthritis (RA) and 450 patients without RA. Population 2 consisted of 155 patients with RA who had long-standing disease. Population 3 consisted of 188 patients with psoriatic arthritis and in population 4 there were 192 patients with systemic lupus erythematosus. Populations 1 and 2 were tested with the anti-human fibrinogen antibody (AhfibA) test, anti-CCP2 from Eurodiagnostica (CCP2-euro), anti-CCP2 from Pharmacia (CCP2-phar) and anti-CCP3 test by Inova (CCP3). Samples were annotated as discrepant if positive in one and negative in at least one other test. Each discrepant sample was re-analysed in a different run. Populations 3 and 4 were analysed in the CCP2-euro and AhFibA test. RESULTS: In population 1, ACPA positivity was found in 17 of 450 (3.8%) patients without RA; 14 (82%) of these 17 samples were discrepant. In contrast, 61 of 86 (70.9%) patients with RA were ACPA positive of whom 18 of 61 (29.5%) were discrepant (70.9% vs. 29.5%, p<0.001). The discrepancies between tests could be partly attributed to borderline results, inter-assay discrepancy and inter-test variability. They were more prevalent in patients with systemic lupus erythematosus who were ACPA positive than in those with psoriatic arthritis who were ACPA positive. CONCLUSIONS: Discrepancy between different ACPA tests was observed attributable to the occurrence of borderline results, inter-assay variability and mainly to inter-test variability. The lowest inter-test discrepancy is observed between tests that use the same substrate.

A Belgian Survey on Geriatric Assessment in Oncology Focusing on Large-Scale Implementation and Related Barriers and Facilitators.

OBJECTIVES: The aim of this study is to describe a large-scale, Belgian implementation project about geriatric assessment (=GA) in daily oncology practice and to identify barriers and facilitators for implementing GA in this setting. Design / setting / participants: The principal investigator of every participating hospital (n=22) was invited to complete a newly developed questionnaire with closed- and open-ended questions. The closed-ended questions surveyed how GA was implemented. The open-ended questions identified barriers and facilitators for the implementation of GA in daily oncology practice. Descriptive statistics and conventional content analysis were performed as appropriate. RESULTS: Qualifying criteria (e.g. disease status and cancer type) for GA varied substantially between hospitals. Thirteen hospitals (59.1%) succeeded to screen more than half of eligible patients. Most hospitals reported that GA data and follow-up data had been collected in almost all screened patients. Implementing geriatric recommendations and formulating new geriatric recommendations at the time of follow-up are important opportunities for improvement. The majority of identified barriers were organizational, with high workload, lack of time or financial/staffing problems as most cited. The most cited facilitators were all related to collaboration. CONCLUSION: Interventions to improve the implementation of GA in older patients with cancer need to address a wide range of factors, with organization and collaboration as key elements. All stakeholders, seeking to improve the implementation of GA in older patients with cancer, should consider and address the identified barriers and facilitators.

[Sézary syndrome with ascitis: case report and review of the literature]. / Ascite associée a un syndrome de Sézary: cas clinique et revue de la littérature.

This case report describes the evolution of a mycosis fungoides into a Sézary syndrome. The originality of the case consists in the appearance of ascitis with Sézary cells during the leukemic phase. It is the second report of a such case. Mycosis fungoides and its leukemic variant, the Sézary syndrome, are primary cutaneous T-cell lymphomas. Their incidence is low. The treatments are topical in the early stages and systemic during the advanced stages. New immunomodulating treatments are in development. The existing therapeutic agents unfortunately do not improve the prognosis of the disease today.

Correlates of fractures in elderly, diabetic outpatients.

It is widely recognized that patients presenting diabetes are at increased risk for fractures. In a retrospective case-control study, 101 cases were selected from medical charts of outpatients older than 70 with diabetes mellitus and a fracture within the past 5 years. Glycosylated hemoglobin (HbA1c) had been measured within 4 months around the assessment. Each case was matched for sex and age with one control, diabetic patient with no fracture. HbA1c level was similar in both groups. Patients with fractures presented significantly lower BMIs than controls, and had a higher rate of declared osteoporosis and comorbidity. A small number of cases were using vitamin D supplements while more were treated with benzodiazepine, opiates and Selective serotonin reuptake inhibitors (SSRI). This study suggests that, rather than the tight control of blood glucose, other factors such as medication and comorbidity could be associated with fracture risk in elderly diabetics.

The increase in zincaemia provoked by starvation does not influence the intestinal absorption of zinc.

Serum zinc, measured in obese patients undergoing two weeks of therapeutic starvation (0 kcal, water ad libitum) increased significantly during the starvation period (+48% at day 10) and returned to prestarvation values after refeeding with a 500 kcal diet. Intestinal absorption of zinc was investigated by an oral zinc tolerance test (with 75 mg of zinc acetate) on the second and the tenth day of starvation. No significant differences were observed between the first and the second test. In our experimental conditions 10 days of starvation failed to induce a loss of zinc exceeding 0.75% of the total body stores. It is concluded that the concentration of zinc in blood per se does not regulate intestinal absorption in the absence of a significant change in zinc requirements.

Interest of zinc determination in leucocyte fractions for the assessment of marginal zinc status.

In order to test the sensitivity of leucocyte zinc determination in the assessment of zinc status, an isolation procedure of mononuclear (MNC) and polymorphonuclear (PMNC) cell fractions was developed. Zinc concentrations in cells from healthy subjects were (mean +/- SD, in mumol/10(10) cells): 0.81 +/- 0.24 in MNC and 0.55 +/- 0.06 in PMNC. In patients suffering from several diseases known to be associated with a marginal impairment in zinc status (cirrhosis, cancer, obesity, endocrine and rheumatic diseases), these concentrations did not differ from those in controls except in rheumatic patients in whom MNC zinc was increased (1.05 +/- 0.42 mumol/10(10) cells) and correlated with erythrocyte sedimentation rate (r = 0.41, P less than 0.01). This relation was also significant in the whole study population (r = 0.39, P less than 0.01). Leucocyte zinc therefore appears to have a limited value in the assessment of marginally impaired zinc status, except in inflammatory states.

Prevalence of inflammatory rheumatic diseases in an adolescent urban student population, age 12 to 18, in Belgium.

In order to determine the prevalence of inflammatory rheumatic diseases in an urban secondary school student population, a questionnaire dealing with past or present joint, tendon, axial, gastrointestinal, ocular and dermatological symptoms was completed by 2,990 students of secondary schools in Antwerp and Ghent. The parents were asked to complete a questionnaire regarding the family medical history. From these 2,990 students, 524 were selected for further investigation by a rheumatology resident, who checked the answers to the first questionnaire and performed a clinical examination. Forty-one adolescents with a presumptive history or present symptoms of inflammatory rheumatic diseases were retained. These students were examined by the medial staff of the rheumatology department; if necessary, a complementary biochemical and radiological examination was performed. Five cases of definite juvenile chronic arthritis (JCA) (with polyarticular onset in 1 case and late pauciarticular onset in 4 cases) and 4 cases of presumptive late pauciarticular onset JCA were detected, resulting in a prevalence of 167 per 100,000 for definite JCA and of 301 per 100,000 for possible JCA. This prevalence rate is higher than that generally described. This method of investigation effectively allows the detection of milder and spontaneously remitting cases of JCA. It further enabled us to definite case and 4 presumptive cases of various previously undiagnosed forms of JCA.

Cyclical pamidronate infusions in postmenopausal osteoporosis.

OBJECTIVES: Until recently, two bisphosphonates, pamidronate (APD) and etidronate were available for clinical purposes. Contrary to etidronate, pamidronate was not extensively studied in osteoporosis. Therefore, we investigated the effect of cyclic intravenous APD treatment in postmenopausal osteoporosis. METHODS: Parameters of bone remodelling and lumbar spine bone mineral density (BMDL) were assessed in 36 postmenopausal women with osteoporosis (BMDL t-score < -2.5). They received five courses of APD. Intervals between courses were defined according to the fasting urinary calcium excretion (UCa/Cr, mg/mg creatinine) which was measured before each APD course and every 2 weeks after the first treatment. The patients were retreated when UCa/Cr had reached baseline levels. Serum biochemical parameters and urinary hydroxyproline (UOHPro/Cr, mg/mg) were measured before each APD. RESULTS: UCa/Cr decreased during 21-28 days after each course but UCa/Cr measured before APD infusion remained unchanged. UOHPro/Cr significantly fell after the third APD (P = 0.02). Serum calcium was however not modified. Parameters of bone remodelling decreased with time: bone-GLA protein (BGP) started to fall after the first APD (P = 0.0001) and continued to decrease until the fourth APD course, alkaline phosphatase (ALP) significantly decreased after the first APD (P = 0.005); intact PTH significantly increased at the fifth APD (P = 0.02). BMDL significantly increased after 1 year treatment: +2.9% of baseline value. CONCLUSIONS: Cyclical pamidronate treatment of postmenopausal osteoprosis appeared to be effective in reducing bone turnover assessed by BGP, ALP and OHPro/Cr. This effect is followed by an increase in vertebral BMD.

Bone mineral density measured by dual photon and dual energy X-ray absorptiometry: a problem of accuracy.

Dual photon absorptiometers (DPA) are currently being replaced by dual energy X-ray absorptiometers (DXA) for measurements of bone mineral density (BMD). In order to evaluate how to use the previously obtained BMD results by DPA (BMDo) in the follow-up of patients, the following study was performed. Ninety-five women who had had BMDo during the last 12 months were selected. L2-L4 BMD was measured twice on the same day using both DPA (BMDp) and by DXA (BMDx). BMDp was highly correlated to BMDx (R = 0.95; P < 0.001) but a wide variation of the ratio BMDp:BMDx was observed which ranged between 0.65 and 1.09 (mean 0.90, S.D. 0.05). There was no significant relationship between the ratio BDMp:BMDx and age or height but there was a significant relationship between this ratio and the weight of the patient (R = 0.31; P < 0.001). The results also indicated that the correlation between DXA and DPA was lower than that observed between the two DPA measurements (R = 0.98; P < 0.001) which, moreover, were not performed on the same day. These observations contrast with the relatively high precision of both instruments and have to be attributed to relative inaccuracy of one or probably both techniques.

Bone mineral content of the spine with dual photon absorptiometry: normalization of the values.

A Novo Industry BMC-LAB 22a densitometer equipped with a 153Gd source was recently implemented for the measurement of bone mineral content (BMC). 70 females (aged 16 to 86 years) and 67 males (aged 20 to 79 years) were selected to form a reference population. Care was taken to exclude patients with an illness or taking a drug that could influence the measurements, made at the lumbar spine level (L2-L4). Normalization procedures using several parameters (age, length, weight, span, lean body mass, an index of obesity, accepted scans) were developed to try and reduce the large interindividual coefficient of variation (CV). Total BMC values were found to yield a larger CV than when expressed as BMC cm-1. The relation of BMC with age showed a significant linear decrease of 0.3% year-1 for the male population. In the female population the BMC was not correlated with age up to the age of 50 years. Thereafter a linear bone loss of 0.76% year-1 was noted. Correcting for length decreased the CV in males and in females younger than 50 years. The use of the other parameters resulted in no or a very slight improvement. Combining parameters in a multiple regression analysis resulted in a significant decrease of the CV in females older than 50 years only.