Preulcerous Risk Situation in Diabetic Foot Syndrome: Proposal for a Simple Ulcer Prevention Score

BACKGROUND

Preulcerous risk situations in patients with diabetes are often undiagnosed and care administered too late. Even with regular medical check-ups and status documentation, foot examinations have not been given enough attention. Diagnosing an individual patients' risk of developing diabetic foot ulcers may increase vigilance for diabetic foot syndrome (DFS), and the appropriate prevention measures matching the risk involved may prevent the emergence of diabetic ulcers. The classical DFS risk factors are well established and have been extensively covered in the literature; however, there is a lack of efficient screening tools that could be used for a rapid assessment of diabetic foot ulcer risk.

METHODS

A methodical literature search was conducted to assess relevant publications for the preparation of a simple risk score for amputation related to diabetic foot ulcer. We then analyzed the risk factors for predictive value as odds ratios in foot ulcers and/or amputation. We used the available data to deduce a mean value to reflect the authors' consensus.

RESULTS

In view of the current literature on the matter, we have developed a semi-quantitative scoring system using just a few items to allow rapid and visual risk assessment for diabetic foot ulcers alongside recommendations for prevention and a sensible follow-up strategy to match the risk.

CONCLUSION

This relatively simple score enables rapid risk classification for patients that can ease the way for both physicians and patients in gaining an insight into individual risk situations. The score provides more effective preventative measures for high-risk patients against future complications.

Effectiveness and Safety of Insulin Glulisine When Initiating Supplementary Prandial Insulin Treatment (SIT) in Insulin-Naïve Patients with Type 2 Diabetes: The Observational IGLU-SIT Study

INTRODUCTION

The IGLU-SIT study documented the effectiveness of initiating supplementary prandial insulin treatment (SIT) with insulin glulisine after failure of oral antidiabetic drugs alone in patients with type 2 diabetes (T2DM) in a real-world setting in Germany.

METHODS

The IGLU-SIT study was an open-label, prospective, multicentre, non-interventional study with an observation period of 12 ± 1 months. The primary objective was to determine the proportion of patients reaching their pre-defined glycosylated haemoglobin (HbA1c) goal at 3, 6, 9 and 12 months. Selected secondary objectives were absolute change in HbA1c, a 7-point blood glucose profile, and rate of hypoglycaemia. Data were evaluated overall and by age group (< 65, 65-74 and ≥ 75 years).

RESULTS

Overall, 215 patients with T2DM were observed in 64 centres. Baseline HbA1c was 8.3%, and mean HbA1c target was 6.8% (baseline 8.1% and target 6.9% in patients ≥ 75 years). Individual HbA1c target attainment in patients peaked at 38.9% (95% confidence interval [CI] 32.1-46.1%) after 12 months; this was 45.9% in patients aged ≥ 75 years. The mean HbA1c reduction was 1.12 ± 1.05% (p < 0.0001) with only minor differences by age group. A 7-point blood glucose profile revealed significant reductions (p < 0.0001) at all time-points. The rate of confirmed symptomatic hypoglycaemia was 2.2% (95% CI 0.7-5.1) during the 12-month follow-up; rates were increased in patients aged ≥ 75 years (7.0%; 95% CI 1.5-19.1) as were the rates of adverse events (17.8 vs. 6.1%).

CONCLUSION

Initiating SIT with insulin glulisine is an appropriate treatment option in patients whose T2DM is insufficiently controlled. Particular attention should be paid to elderly patients in whom higher attainment rates of treatment target were associated with adverse events.

TRIAL REGISTRATION

https://awbdb.bfarm.de ; Identifier: 6819; Date of registration: 23.06.2016.

Effectiveness and Safety of Switching Rapid-Acting Insulins to Insulin Glulisine in Patients with Diabetes: The Observational IGLU-S Study

INTRODUCTION

The IGLU-S study assessed the effectiveness of insulin glulisine after switching from human insulin/other rapid-acting insulin analogues in patients with type 1 diabetes (T1DM) and type 2 diabetes (T2DM) in a real-world setting in Germany.

METHODS

Open-label, prospective, multicentre, non-interventional study in Germany. The primary outcome was proportion of patients reaching pre-defined glycosylated haemoglobin A1c (HbA1c) goal at 3, 6, 9 and 12 months. Secondary outcomes included absolute changes in HbA1c, rate of hypoglycaemia and 7-point blood glucose profiles.

RESULTS

Overall, 432 (55 T1DM, 377 T2DM) patients were enrolled. Baseline HbA1c was 8.2% (T1DM) and 8.3% (T2DM); individual HbA1c targets were 6.8% and 6.9%, respectively. After insulin glulisine introduction, the proportion of patients achieving their individual HbA1c increased to 43.6% (T1DM) and 39.6% (T2DM) of patients at 12 months. At 12 months, mean HbA1c was reduced by 0.86 ± 1.03% (p < 0.0001) in T1DM and 1.01 ± 1.02 (p < 0.0001) in T2DM. The 7-point blood glucose profile showed a significant reduction in patients with T2DM (p< 0.0001) and a non-significant reduction in T1DM patients. Confirmed symptomatic hypoglycaemia was 5.7% (T1DM) and 1.6% (T2DM). There were no cases of severe hypoglycaemia.

CONCLUSION

Switching prandial insulin to insulin glulisine resulted in improved effectiveness with 43.6% of T1DM and 39.6% of T2DM patients reaching their individual pre-defined HbA1c target within 1 year. Switching was safe and was associated with a low rate of hypoglycaemia and adverse events.

TRIAL REGISTRATION

https://awbdb.bfarm.de ; Identifier: 6818; Date of registration: 23.06.2016.

A Difference Between Bedtime and Pre-Breakfast Plasma Glucose Levels Indicates the Need for Prandial Insulin in Basal Insulin-Treated Type 2 Diabetic Patients with Normal Fasting Glucose

AIM

In the present analysis, we characterised the efficacy and safety of adding a single daily injection of insulin glulisine to optimised basal-supported oral therapy (BOT) in patients with a high BeAM value, defined as a more than 50 mg/dl difference between bedtime and pre-breakfast blood glucose.

METHODS

The BeAM value was retrospectively calculated for patients pooled from two clinical trials that supplemented BOT with glulisine. Data regarding changes in HbA1c, fasting plasma glucose (FPG), and postprandial glucose (PPG) levels from observation periods of 3 to 6 months were assessed.

RESULTS

Out of 358 patients that received BOT/glulisine, 182 had a high BeAM value. Patients with a high BeAM value were older and had a longer diabetes duration than patients with a medium BeAM value. Significant reductions in HbA1c (7.5% to 7.2% [59 to 55 mmol/mol], p<0.0001) and PPG (202 to 143 mg/dl, p<0.0001) levels were documented. The proportion of patients with a high BeAM value achieving an HbA1c <7% [53 mmol/mol], alone or in combination with no hypoglycaemia, was lower than that of patients with a medium BeAM value.

CONCLUSION

The analysis indicates that the supplementation of BOT with a single daily injection of prandial insulin is safe and effective for reducing HbA1c and PPG levels in patients with a high BeAM value (more than 50 mg/dl). However, patients with a medium BeAM value also responded well, which suggests that they should also be considered candidates for this change in therapy.

Titration of insulin glargine 100 U/mL when added to oral antidiabetic drugs in patients with type 2 diabetes: results of the TOP-1 real-world study

AIMS

Adequate insulin titration is crucial for optimal glycaemic control in type 2 diabetes (T2D). We aimed to explore the factors and outcomes associated with titration of glargine 100 U/mL (Gla-100) in patients uncontrolled on oral antidiabetic drugs (OAD) and initiating insulin therapy.

METHODS

Patients from the Titration and Optimization (TOP)-1 registry were stratified by the magnitude of Gla-100 up-titration during the first month (no [< 1 Units (U)/day (d)], minimal [≥ 1 and < 5 U/d], moderate [≥ 5 and ≤ 8 U/d] and strong [> 8 U/d]). The primary endpoint was a fasting blood glucose (FBG) ≤ 110 mg/dL on ≥ 2 occasions and/or individual HbA1c target by 12 months.

RESULTS

Of 2308 patients, 905, 715, 409 and 279 underwent no, minimal, moderate and strong titration, respectively. Age decreased across increasing titration groups (p = 0.02) while body mass index (BMI) (p < 0.0001), FBG (p < 0.0001), and HbA1c (p < 0.0001) increased. At 12 months, the proportions of patients achieving the primary endpoint were comparable across groups (66.1% overall), though a smaller proportion of no titration patients met both their individual HbA1c target and FBG ≤ 110 mg/dL compared to moderate and strong titration patients (20.1% vs. 27.2% and 26.2%, p = 0.033 and 0.023, respectively). HbA1c was also comparable, though FBG was higher in the no titration group (126.2 vs. 122.6, 121.5 and 120.9 mg/dL, p < 0.02). A similar, small reduction in body weight occurred in all groups; hypoglycaemia rates were comparable across groups.

CONCLUSIONS

In real-world, titration of Gla-100 during the first month appears to coincide with a number of baseline factors. Insulin dose to meet HbA1c and FBG targets remains suboptimal in the majority of T2D patients.

Predictors of treatment response in type-2 diabetes patients initiating basal-supported oral therapy with insulin glargine 100 U/mL: A sub-analysis of the Titration and OPtimisation (TOP) registry

The aim of this study was to identify predictors of long-term response to the initiation of basal-supported oral therapy (BOT) with insulin glargine (IGlar-100). Patients from the observational TOP registry were grouped based on those who had achieved (responders) and those who had not achieved (non-responders) their HBA1c target and/or FBG ≤110 mg/dL 12 months after IGlar-100 initiation. Independent predictors of treatment response were identified by regression analysis. Data for 2444 patients were analysed (responders, n = 1610; non-responders, n = 834). Although the IGlar-100 dose increase over 12 months was larger for non-responders (+12.83 vs +9.46 U/d; P < 0.0001), the corresponding decrease in HbA1c was smaller (-0.88% vs -1.57%). Independent predictors of response included lower BMI (OR, 0.97; 95% CI, 0.95-1.00), lower FBG (OR, 0.98; 95% CI, 0.97-0.98) and HbA1c values at baseline (OR, 0.24; 95% CI, 0.18-0.31), a less ambitious HbA1c target (OR, 5.07; 95% CI, 3.37-7.63) and bedtime administration of IGlar-100 (OR, 1.55; 95% CI, 1.12-2.14). In conclusion, HbA1c was the clinically most significant baseline characteristic predictive of response to BOT. This may suggest an advantage of IGlar-100 initiation prior to excessive hyperglycaemia escalation.

Wann mit der intensivierten Insulintherapie beginnen? – Der BeAM-Wert zur besseren Abschätzung einer prandialen Insulintherapie bei Typ-2-Diabetes mellitus

Der BeAM-Wert ist ein kumulatives Maß der postprandialen Hyperglykämie. Er lässt sich aus der Blutglukosekonzentration vor dem Zubettgehen (Be) und der darauf folgenden Nüchternglukose am Morgen (AM) errechnen. In zwei retrospektiven Auswertungen von Daten aus Phase-III- und -IV-Studien wurde der Nutzen des BeAM-Wertes als Entscheidungshilfe für den Beginn der intensivierten Insulintherapie bei Typ-2-Diabetes mellitus (T2DM) Patienten unter basalinsulinunterstützter oraler Therapie (BOT) dargelegt.

Bei Patienten, deren Therapie von einer oralen antidiabetischen Therapie (OAD) auf eine basalinsulinunterstützte orale Therapie umgestellt wird, steigen Ausmaß der postprandialen Hyperglykämie und der BeAM-Wert an bei gleichzeitig sinkendem HbA1c-Wert und Nüchternglukose. Nach Umstellung auf eine intensivierte Insulintherapie fällt der BeAM-Wert und das Ausmaß der postprandialen Hyperglykämie geht zurück.

Insbesondere Patienten mit einem BeAM-Wert > 50 mg/dl profitieren von der Umstellung auf eine intensivierte Insulintherapie. Ein negativer BeAM-Wert spricht gegen den Einstieg in die prandiale Insulintherapie.

Titration and optimization trial for the initiation of insulin glargine 100 U/mL in patients with inadequately controlled type 2 diabetes on oral antidiabetic drugs

For patients with type 2 diabetes mellitus (T2DM) and inadequate glycaemic control, addition of basal insulin is recommended, but titration and optimization of basal insulin therapy in primary care is not well understood. We conducted an observational trial in 2470 patients with T2DM who initiated insulin glargine 100 U/L (Gla-100) on top of oral antidiabetic drugs. Physicians were free to choose either a "Davies," "Fritsche" or "individual" titration algorithm. We found that fasting blood glucose (FBG) and glycated haemoglobin (HbA1c) levels were effectively reduced by Gla-100; 65.9% of patients achieved the primary endpoint (FBG ≤6.1 mmol/L (110 mg/dL) or an individual HbA1c target). There were no significant differences in efficacy and safety between the algorithms used. The mean FBG decreased by 3.2 mmol/L (59 mg/dL) over 12 months, while the mean HbA1c decreased by 15.3 mmol/mol (1.4%)%. From a starting dose of 11.7 U/d, the Gla-100 dosage was 22.8 U/d at 12 months, with similar values in each group. Rates of hypoglycaemia were low and did not differ by titration algorithm. We conclude that Gla-100 was effective at reducing FBG and HbA1c, independent of the titration algorithm, but observed that algorithms were inconsistently applied in clinical practice.

Addition of a single short-acting insulin bolus to basal insulin-supported oral therapy: a systematic review of data on the basal-plus regimen

We summarize here clinical and trial data on a once-daily administration of a single bolus to the meal with the largest expected postprandial glucose excursion (basal-plus), and comment on its clinical utility in the treatment of type 2 diabetes. A PubMed search of data published until September 2018 was taken into consideration and PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed. Eighteen reports representing 15 studies were identified (age: 18-80 years; 50-890 patients; follow-up: 8 days to 60 weeks). Data suggest basal-plus is efficacious for improving glycemic control, with a low incidence of (severe) hypoglycemia and minor increases in bodyweight. The timing of short-acting insulin administration and use of different monitoring/titration approaches appear to have minimal impact. When compared with premixed insulin, basal-plus results in largely comparable outcomes. Compared with basal-bolus, it may result in non-inferior glycemic improvements with less weight gain, less hypoglycemia and fewer daily injections. A basal insulin/glucagon-like peptide-1 receptor agonist fixed ratio combination may offer several advantages over the basal-plus regimen, at the cost of gastrointestinal side effects. We conclude that the stepwise introduction of short-acting insulin via the basal-plus strategy represents a viable alternative to a full basal-bolus regimen and may help to overcome barriers associated with multiple injections and anticipated complexity of the insulin regimen.

HbA1c target achievement in the elderly: results of the Titration and Optimization trial for initiation of insulin glargine 100 U/mL in patients with type 2 diabetes poorly controlled on oral antidiabetic drugs

OBJECTIVES

To identify real-world, age-related trends in the use of insulin glargine 100 U/mL (Gla-100) as part of basal-supported oral therapy (BOT).

RESEARCH DESIGN AND METHODS

The prospective, observational Titration and Optimization registry enrolled patients with poorly controlled type 2 diabetes mellitus initiated on Gla-100 BOT. The primary outcome was the proportion of patients with capillary fasting blood glucose (FBG) ≤110 mg/dL on ≥2 occasions and/or who met their individual HbA1c target within 12 months.

RESULTS

2462 patients were analyzed (<65 years: n=1122; 65-74 years: n=771; ≥75 years: n=569). Diabetes duration (6.8, 8.9, and 11.2 years, p<0.0001) and proportion of women (40.7%, 47.9%, and 55.7%, p<0.0001) increased with age. Baseline HbA1c was highest in <65-year-olds (8.6% vs 8.4% and 8.5%, p<0.0001). Gla-100 up-titration until 12 months was highest in <65-year-olds (+11.6 U/day), compared with 65-74 (+10.2 U/day) and ≥75 years (+8.8; p<0.0001) but similar by units per kilogram, as was the decrease in FBG (<65: -64.1 mg/dL; 65-74: -56.1 mg/dL; ≥75: -53.4 mg/dL) and HbA1c (<65: -1.47%; 65-74: -1.31%; ≥75: -1.22%, p<0.0001). At 12 months, 65.9% of participants met the primary endpoint, with no significant difference between age groups. The proportion achieving their individual HbA1c target was lower for <65-year-olds (46.0% vs 54.3% and 54.7%; p<0.02). Symptomatic hypoglycemia incidence was more common in the ≥75-year-old group (3.4% vs 1.4% and 1.4%; p=0.0126).

CONCLUSIONS

BOT with Gla-100 results in similar improvements of glycemic values with low risk of hypoglycemia across age groups. Given the link between HbA1c and long-term cardiovascular risk, ensuring appropriately stringent target-setting, intensification of basal insulin and making sure hypoglycemia is avoided is of paramount importance.

TRIAL REGISTRATION NUMBER

Database: https://awbdb.bfarm.de; Identifier: 1641; Date of registration: September 23, 2013.

A higher blood glucose level pre-breakfast in comparison to bedtime is a contraindication for intensification of prandial insulin therapy in patients with type 2 diabetes - The impact of a negative BeAM value

Aims

The BeAM value refers to the difference between a patient’s blood glucose level at bedtime (Be) and the following morning before breakfast (AM). The clinical impact of a negative BeAM value (AM blood glucose reading compared to that taken at bedtime) is unknown.

Methods

T2DM patients of the OPAL and POC trials were pooled and their BeAM values calculated.

Results

From a total of 358 patients, 31 were calculated as having a negative BeAM value at baseline, while 182 had a high value. Patients in the negative BeAM group were younger, had shorter diabetes duration, and lower HbA1c levels. Fasting blood glucose levels were higher in the negative BeAM group, and these increased to a greater extent during the trial periods. No significant differences in hypoglycaemia occurrence were observed. Multivariate adjusted analysis indicated no association between a negative BeAM value and achievement of HbA1c < 7%, or composite endpoints that additionally included no hypoglycaemia and no weight gain.

Conclusions

Supplementation of BOT with prandial insulin is not beneficial for patients who have a higher blood glucose reading before breakfast in comparison to before bedtime. Further investigation into the cause of the high morning reading in these patients is indicated.

Titration of basal insulin or immediate addition of rapid acting insulin in patients not at target using basal insulin supported oral antidiabetic treatment - A prospective observational study in 2202 patients

AIM

Optimal treatment intensification strategies in patients with type-2 diabetes mellitus (T2DM) receiving basal insulin supported oral antidiabetic therapy (BOT) remain controversial. The objective of the present study was to compare outcomes of BOT-intensification by either the uptitration of long-acting insulin glargine or by the immediate addition of a rapid acting insulin analogue (RAIA).

METHODS

This was a prospective, observational, 24-week study in T2DM patients with BOT using insulin glargine and baseline glycated hemoglobin (HbA1c) between 7.0 and 8.5%. Patients were stratified by their physicians to one of the following treatment intensification strategies: Basal insulin titration to target with discretionary subsequent addition of RAIA at weeks 12 or 24 (GLAR), or immediate addition of RAIA at baseline (GLARplus).

RESULTS

A total of 3266 patients were prescreened of whom 2202 fulfilled the selection criteria. Of these, 1684 patients were documented in the GLAR group and 518 in the GLARplus group. In the GLAR group, in 91 (5.5%) and 21 patients (1.3%) RAIA was added at weeks 12 and 24, respectively. The groups displayed similar baseline characteristics; except, mean diabetes duration was slightly shorter in the GLAR group (8.7 vs. 9.4 years). During the study, insulin glargine dose was increased from 18.7 to 26.4U (plus 7.7U) in GLAR and from 24.9 to 27.3U (plus 2.4U) in GLARplus patients. Mean RAIA dose was 9.6±4.7U at the final visit. After 24 weeks, HbA1c was reduced by 0.8 and 0.9% in the GLAR and GLARplus groups, respectively (both p<0.001). An HbA1c of ≤7.0% was achieved in 49.2% of GLAR and 48.5% of GLARplus patients. In both groups, we observed improvements in cardiovascular risk factors such as lipids and blood pressure. The rates of symptomatic (1.6 vs. 1.7%) and severe (0.18 vs. 0.19%) hypoglycemic episodes were low and comparable in both groups.

CONCLUSION

These findings provide evidence that treatment intensification in patients with type 2 diabetes not at glycemic target on BOT with insulin glargine is equally safe and effective using either long-acting insulin titration alone or the addition of a rapid-acting insulin analogue.

Composite efficacy parameters and predictors of hypoglycaemia in basal-plus insulin therapy--a combined analysis of 713 type 2 diabetic patients

AIMS

We aimed to identify predictors of hypoglycaemia in patients with poorly controlled type 2 diabetes treated with a single daily bolus of insulin glulisine on top of insulin glargine and oral antidiabetic drugs (basal-plus regimen).

METHODS

We retrospectively analysed four large basal-plus trials including 713 patients (47% female) with type 2 diabetes, mean age of 59.9 ± 9.5 years and diabetes duration of 11 ± 7.0 years. Predictors for symptomatic, severe and nocturnal hypoglycaemia were identified by multivariate logistic regression analyses, calculation of odds ratios (ORs) and Wald 95% confidence intervals (CIs).

RESULTS

Mean numbers of hypoglycaemic events per year were 4.64 ± 11.4 (symptomatic < 60 mg/dl), 0.59 ± 2.28 (nocturnal) and 0.03 ± 0.22 (severe). A total of 44.5% of patients reached the composite endpoint of glycated haemoglobin (HbA1c) <7.0% plus no severe hypoglycaemia, and 26.7% reached the composite of HbA1c <7.0% plus no symptomatic hypoglycaemia. Predictors of nocturnal and symptomatic hypoglycaemia were female gender (OR 1.82; 95% CI 1.07-3.11 and OR 1.89; 95% CI 1.31-2.78), diabetes duration >10 versus <5 years (OR 2.61; 95% CI 1.03-6.59 and OR 2.01; 95% CI 1.15-3.51) and higher basal insulin dose (per unit of increase) (OR 1.01; 95% CI 1.00-1.03 and OR 1.01; 95% CI 1.00-1.02). Conversely, a higher body mass index (BMI) (27-30 vs. <27 kg/m(2) and >30 vs. <27 kg/m(2) ) conferred a reduced risk of symptomatic hypoglycaemia with an OR of 0.53 (95% CI 0.31-0.90) and an OR of 0.61 (95% CI 0.39-0.97).

CONCLUSIONS

Female gender, a long diabetes duration and higher basal insulin dose were predictors of hypoglycaemia, while protection was provided by BMI > 30. These results may help to successfully establish basal-plus insulin regimen in individual patients on their transition from basal-only to basal-bolus treatment.

Assessment of the mixing efficiency of neutral protamine Hagedorn cartridges

Reliable application of neutral protamine Hagedorn (NPH) insulin requires previous resuspension of the suspension by tipping over the cartridge 20 times. This procedure is considered annoying by patients. The goal of this investigation was to assess the efficiency of the mixing procedure when performed less frequently than recommended. Neutral protamine Hagedorn insulin cartridges from five different manufacturers (sanofi-aventis, Lilly, Berlin-Chemie, B. Braun, and Novo Nordisk) were emptied with doses of 28 IU in the morning and the evening over 5 days. While the first dose was obtained after a regular resuspension procedure (20x tipping over), the consecutive doses were obtained after 3, 6, 10, or 20 mixing procedures (12 cartridges per experimental series, two doses/day). Insulin concentrations of doses 1, 2, 6, and 10 were determined by high-pressure liquid chromatography. Between dosing, cartridges were stored at room temperature in a horizontal position. Comparable insulin concentrations were seen in the first correctly prepared doses. Pronounced and substantial deviations from the selected dose were observed with most of the cartridges, in particular when resuspending only 3 and 6 times. Mean absolute percentage deviations when tipping 3 times and maximally observed overdoses were: Insuman basal: 1.1 +/- 1.0%/4 IU, Humulin N: 2.6 +/- 3.4%/19 IU, Berlinsulin H basal: 4.4 +/- 6.0%/26 IU, Insulin B. Braun basal: 10.4 +/- 8.9%/38 IU, and Protaphane: 4.7 +/- 4.1%/19 IU (all p < 0.05 vs Insuman basal). Only one cartridge with three metal mixing bullets (sanofi-aventis) was resuspended efficiently with only a few mixing procedures. All other cartridges with fewer bullets were shown to deliver potentially harmful doses if used for treatment when the mixing procedure was less frequent than demanded in the instructions for use.

Exposure of cardiac fibroblasts to the herbicide nitrofen causes altered interactions with the extracellular matrix

A large proportion of congenital heart defects result from dysmorphogenesis of valvuloseptal precursors, the endocardial cushions. Intrinsic to formation and maturation of these tissues are developmental changes in cell-cell and cell-extracellular matrix interactions. Interactions between cells and the extracellular matrix play critical roles in modulating cellular processes including proliferation, migration, differentiation and even survival. While significant progress is being made in the elucidation of the cellular events involved in valvuloseptal development, little is known regarding how environmental factors may affect this process. Embryonic exposure to the herbicide nitrofen has been shown to result in congenital heart defects associated with altered endocardial cushion formation or maturation. The present studies were performed to begin to address the cellular mechanisms of these nitrofen-induced effects. Heart fibroblasts were isolated and treated with varying doses of nitrofen in vitro. Experiments were performed to determine the effects of this herbicide on important cellular processes including migration, proliferation and apoptosis. These studies illustrated a dose-dependent decrease in collagen gel contraction and proliferation in response to nitrofen. Assays were also performed to determine the effects of nitrofen on fibroblast gene expression. Increased expression of collagen type I and specific integrins were seen following nitrofen exposure. These studies illustrate that nitrofen has direct effects on cardiac fibroblast proliferation and extracellular matrix remodeling, cellular events important in valvuloseptal development.