1. 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

2. 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.

3. 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, …)

4. Methods (1) Design : retrospective cross-sectional study Subjects :
Eligible: (n = 229)
consecutive EP (75+ yrs) with type 2 diabetes
admitted to the G division ( – )
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:

5. 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:

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

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

8. 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 [ ]
Male gender
51% (74)
38% (17)
1.74 [ ]
ADL dependence
29% (42)
24% (11)
1.55 [ ]
Cognitive dis.
66% (95)
58% (26)
1.42 [ ]
Comorb. (4+syst)
58% (84)
1.03 [ ]
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 [ ]
3.41 [ ]
0.29 [ ]

9. 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 [ ]
falls (< 1 yr)
42% (60)
40% (18)
1.07 [ ]
hypertension
80% (36)
0.75 [ ]
obesity
08% (11)
03% (06)
0.53 [ ]
GFR<50
37% (53)
44% (20)
0.72 [ ]
Insulin
19% (28)
38% (17)
0.11 [ ]

10. 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)

11. 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

12. 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

13. 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 ?

14. & 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