Low glycated haemoglobin (HbA1C) in geriatric patients with type 2 diabetes : prevalence & correlates Benoit Boland °, Pauline Cavrenne * Geriatrician °, Hopital Pharmacist * Geriatric division, St-Luc University Hospital, UCL BVGG meeting, Oostende 06.02.2009

Background: type 2 diabetes Adult onset Elderly onset Prevalence ~ 4 % > 10 % Insulin resistance Insulin secretion ↑ ↔ ↓ µicrovascular benefits hypoGlycemia risks risks-benefits ratio Target for HbA1C Glucose lowering drugs + + ± low < 7 % OAD ± Insulin + + * high 7.5 % – 8.5 % ° * Cognitive dysfunction. Shorr et al. , JNHA 2006 ; Falls : Nelson et al. JAGS 2007 ° EUGMS guidelines, 2004: type 2 diabetes mellitus. www.eugms.org/academic/guidelines

Aims of the study To determine the prevalence of low HbA1C in frail elderly diabetic patients Hypothesis: Frail diabetic EP often have low HbA1C To identify patient’s characteristics associated with low HbA1C Hypothesis: Frail diabetic EP with low HbA1C present with less Insulin Resistance features (obesity, hypertension, …)

Methods (1) Design : retrospective cross-sectional study Subjects : Eligible: (n = 229) consecutive EP (75+ yrs) with type 2 diabetes admitted to the G division (01.2005 – 09.2008) with HbA1C measurement Exclusion: none of the 4 EUGMS frailty criteria * (n = 30) ADL dependency (washing, clothing) Co-morbidity (4+ systems) Cognitive disorders (dementia or MMSE < 24/30) NH residency Inclusion: (n = 189) * Type 2 diabetes mellitus, guidelines 2004: www.eugms.org/academic/guidelines

Methods (2) Data sources Endpoint : low HbA1C : < 7.5 % * Analyses Hospital biochemical data bank Geriatric medical records Endpoint : low HbA1C : < 7.5 % * Analyses Patient’s characteristics: proportions, mean ± SD Comparisons: low vs. normal/high HbA1C (p-values) Associations (n=14): Odds Ratios & 95% CI * Type 2 diabetes mellitus, guidelines 2004: www.eugms.org/academic/guidelines

Results (1) Patient’s characteristics, n=189 Age (yrs) 83 ± 5 Gender, women 52 % Living at home 74 % With spouse 46 % Alone 28 % Nursing Home 26 % Cog disorders 64 % Comorbidity (4+) 58 % ADL dependency 28 % Falls (< 1 year) 41 % HbA1C, % 6.9 ± 1.6 MDRD, ml/min 60 ± 29 Systems, nb 3.8 ± 1.2 Medications, nb 6.5 ± 3 Polymedication, 5+ 73 % Hypertension 76 % Obesity 9 % GLDrugs, any 84 % OADrug 65% Insulin 24 %

Results (2) HbA1C distribution 43% 33% 10% 13%

Results (3) Correlates of low HbA1C 76% (n=144) HbA1C >7.5% 24% (n=45) OR [95%CI] Old old (85+ yrs) 44% (64) 29% (13) 1.97 [0.95-4.06] Male gender 51% (74) 38% (17) 1.74 [0.87-3.45] ADL dependence 29% (42) 24% (11) 1.55 [0.77-3.13] Cognitive dis. 66% (95) 58% (26) 1.42 [0.71-2.81] Comorb. (4+syst) 58% (84) 1.03 [0.52-2.01] Nursing Home Home, with spouse Home, alone 25% (36) 69% (74/108) 31% (34/108) 31% (14) 39 % (12/31) 61% (19/31) 0.73 [0.35-1.54] 3.41 [1.50-7.81] 0.29 [0.13-0.66]

Results (4) Correlates of low HbA1C 76% (n=144) HbA1C >7.5% 24% (n=45) OR [95%CI] p-value < 0.05 medicat° 5+ 75% (108) 66% (30) 1.50 [0.72-3.10] falls (< 1 yr) 42% (60) 40% (18) 1.07 [0.54-2.12] hypertension 80% (36) 0.75 [0.33-1.71] obesity 08% (11) 03% (06) 0.53 [0.18-1.54] GFR<50 37% (53) 44% (20) 0.72 [0.37-1.43] Insulin 19% (28) 38% (17) 0.11 [0.04-0.29]

Discussion (1) Characteristics of these elderly frail diabetic patients few obese (9%) « few » women (52%) Prevalence of low HbA1C : very high Correlates of low HbA1C possibly causes Risk factor : age 85+ (OR 2.0 ; p=0.07) Protective factors: insulin (OR 0.11 ; p<0.01) alone at home (OR 0.29 ; p< 0.01) possibly consequences not found (e.g. Cg disorders, hx of falls)

Discussion (2) Strengths Weaknesses Study size (45 months) Many GPractices (>100) Only frail patients Data from G reports Weaknesses Transveral design Lack of some data e.g. DB duration, … Generalisation EUGMS guidelines Precision No causative assumption

Perspectives To study the link between low weight & low HbA1C Hypothesis: EP with diabetes and denutrition have even lower HbA1C To analyse the determinants of dosage diminution of Glucose Lowering Drug (GLD) upon hospital discharge Hypothesis: In diabetic EP with daibetes and low HbA1C, GLD diminution is more frequent if Geriatric Syndromes are present

Messages In frail EP with OADrugs HbA1C measurements (frequency ?) Reminders for HbA1C target (7.5 – 8.5 %) Dosage diminutions, or even cessation  Withdrawing of Oral Anti-diabetic Drugs ? In EP with elevated glycaemia but no GLDrug Assessment of life expectancy & frailty Risk-Benefit evaluation  Withholding of Oral Anti-diabetic Drugs ?

& suggestions for OAD prescriptions ? In EP with no known diabetes If hyperglycemia, do not start OAD quickly : WAIT & SEE If OAD is decided, start low (dosage) and … STAY LOW In EP with known diabetes and receiving OADrugs Monitor HbA1C : … BE CAREFUL THE LOWER HbA1C is … NOT THE BETTER